Please enter your email address and we’ll send you a link to reset your password right away.

Your VIP area awaits in the APP

Apple Store Google Play

Log in to the app to manage your account, orders, and exclusive benefits.

Order tracking

Order tracking

Personalized notifications

Personalized notifications

Exclusive offers

Exclusive offers

Staying signed in lets you shop faster, check your orders, and access your favorites without signing in again.

Stay signed in
Log out
top

Sold and shipped by

sales

Free shipping

Return of order

Homepage
Back to PC configurator
C4

C4 Naifu S knife

Price without code 24.99

RRP:

You save:

Price without subscription

VAT & duties included

10 Reviews

|

21 Questions

No extra charges at delivery.

What is my size?

What is my size?

My virtual fitting room

My virtual fitting room

The delivery date gives you an indication of how long it will take to receive the item. It´s based on the preparation time, the delivery service selected on the Shopping Basket page and when we receive cleared payment.

Single purchase

Add to my pack 

You save:

Buy now in 1 click
Back to PC configurator

Buy this product and earn

Color:

Free shipping

dto_trans discount on shipping

Free assembly

Free removal of old appliance (only with Ader)

Your interest-free financing from with Klarna Paypal

Pay in 3, 4, 6 or up to 12 installments

My virtual fitting room

Other colors available

left
right

Perfect pairings

left
right

Reportar error

Trusted by over 25 million satisfied customers worldwide

Official brand warranty

Quick & easy 30-day return

Features of C4 Naifu S

Product description of C4 Naifu S knife

Description summary

NAIFU and NAIFU S feature an innovative and ergonomic design. NAIFU is a belt knife with a total length of 204mm and a blade length of 94mm. NAIFU S is a smaller knife, designed to be carried on the arm, with a total length of 144mm and a blade length of 66.5mm. The handle and the sheath are manufactured in recyclable POM material. This is a very sturdy and autolubricating material with excellent mechanical properties and low water absorption. NAIFU has a locking system between the knife and the sheath which makes it for an easy extraction and insertion. The blade of NAIFU S is inserted all the way in the handle making it extremely sturdy. NAIFU’s blade features a shaft remover and comes out from the bottom of the blade so that it can be used as a light hammer. A very important feature on the NAIFU knives is that the blade is machined to create a razor cutting edge whose geometry greatly increases its cutting and penetrating effect. Both knives are delivered with two rubber straps with stainless steel buckles for use on the arms or legs. NAIFU sheath also features two holes on the bottom so that an additional elastic can be used to hold the knife in position.

Specifications

Manual

Technical specifications of C4 Naifu S

Features of C4 Naifu S

Color Black

Color

Black

Recommended Use Spear Fishing

Recommended Use

Spear Fishing

Product Type Knives

Product Type

Knives

Key differentiators

Compact, lightweight design (240g) ideal for arm or weight belt mounting.

Equipped with a reliable locking mechanism and safety lock for secure storage.

Ergonomic handle and sheath made from durable POM material.

Features a sharp, pointed blade with a straight cutting edge for efficient cutting.

Includes a sheath and two rubber straps for versatile carrying options.

Technology in C4 Naifu S knife

Energy rating

Warnings

4.9 / 5

10 Reviews

What our customers are saying about C4 Naifu S knife

This compact dive knife offers excellent quality and sharp performance. Its small size is ideal for arm mounting, ensuring safe and convenient access during dives. The reliable locking system and sharp blade are praised, though some find the blade length a bit short. The finishes are noted as very good for this lightweight and compact safety knife

C4 Naifu S knife

Excellent product

2025/09/26

Francesco

Excellent product...even though it's small, it does its job. I made the smooth side of the blade sharper to make any cuts easier. I recommend it.

C4 Naifu S knife

Too small

2022/12/24

Bruno Barros

Good quality and well finished but too small for my taste. They put the measurements so it's my fault 100%.

C4 Naifu S knife

C4 naifu S black

2021/09/29

Seahunter

Sharp point knife. Have rubber lock at the sheath. The rubber strap not too help the knife to it’s position. I more prefer stick it to the weight belt. Thanks me later

C4 Naifu S knife

C4 Naifu S

2020/12/10

Gunnar B Fjelstul

very good knife, smaller than expected

C4 Naifu S knife

Good

2020/08/05

Clément

Good knives hold well in the case for the moment, a little hard caught the first exit then after it goes, to see if big glove the winter will need maybe to add a string on the end of the handle

C4 Naifu S knife

Knife c4

2020/07/26

Francisco

Very good knife with good finishes small and compact perfect for the arm or the belt

C4 Naifu S knife

C4 Naifu S

2020/02/29

Dzmitry

C4 Naifu S small, use as spar knife for safety, very light , actual price.

C4 Naifu S knife

C4 Knife

2026/04/17

Fatih

The knife is perfect size is really good it’s small and very easy to use it quick.

C4 Naifu S knife

Good quality!

2022/09/11

Amorim

Very small, is the perfect size for using in the arm. The locking system is very simple but reliable. The blade is a little too short but it's very sharp. Overall good quality.

C4 Naifu S knife

Knife top

2021/05/21

Maurício Viana Corrêa

Perfect knife to use on your arm more safely on dives, excellent quality

Write a review about this product

Answer the question

Write your answer

The question has already been answered, thank you very much for trying to help another customer. We will count on you for future questions.

Include AI Generated questions and answers

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What are the main features of the C4 Naifu S dive knife?

Answer of Generated by AI and verified

The C4 Naifu S is a compact and lightweight dive knife designed for easy access and reliability. It features a sharp, straight-edged blade with a fine point, an ergonomic handle, and a secure locking mechanism. The knife comes with a sheath and two rubber straps for arm or weight belt mounting.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What materials are used to make the C4 Naifu S knife and its sheath?

Answer of Generated by AI and verified

The handle and sheath of the C4 Naifu S are manufactured from recyclable POM (Polyoxymethylene). This material is noted for being sturdy, self-lubricating, and having low water absorption.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

Is the C4 Naifu S knife designed to be ergonomic?

Answer of Generated by AI and verified

Yes, the C4 Naifu S features an innovative and ergonomic design to ensure comfortable and secure handling during use.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

Does the C4 Naifu S come with a sheath?

Answer of Generated by AI and verified

Yes, a sheath is included with the C4 Naifu S knife. It features a reliable locking system to hold the knife securely in place.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What type of locking mechanism does the C4 Naifu S have?

Answer of Generated by AI and verified

This knife is equipped with a locking mechanism that secures the knife in its sheath, allowing for easy extraction and insertion while ensuring it stays in place.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What is the blade tip type on this knife?

Answer of Generated by AI and verified

The C4 Naifu S features a pointed blade tip, designed for precision.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What is the weight of the C4 Naifu S knife?

Answer of Generated by AI and verified

The product weight of the C4 Naifu S knife is 240g.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What is the cutting edge type of the C4 Naifu S blade?

Answer of Generated by AI and verified

The C4 Naifu S has a straight cutting edge. The blade is machined to create a razor cutting edge for increased cutting and penetrating effect.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What is the recommended use for the C4 Naifu S knife?

Answer of Generated by AI and verified

The C4 Naifu S is specifically recommended for spear fishing. Its compact size and sharp blade make it suitable as a primary or spare safety knife for divers.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

How can I mount or carry the C4 Naifu S knife?

Answer of Generated by AI and verified

The C4 Naifu S is designed for versatile carrying options. Its compact size makes it ideal for mounting on your arm or a weight belt, and it comes with two rubber straps to facilitate this.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

Is this knife suitable for adults?

Answer of Generated by AI and verified

Yes, the C4 Naifu S is designed for adult users.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What materials are used to make the C4 Naifu S knife and its sheath?

Answer of Generated by AI and verified

The handle and the sheath of the C4 Naifu S are both manufactured from recyclable POM material. This is a sturdy, autolubricating material known for its excellent mechanical properties and low water absorption.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

Is a sheath included with the C4 Naifu S knife?

Answer of Generated by AI and verified

Yes, a sheath is included with the C4 Naifu S knife. The sheath features a reliable locking system to hold the knife securely and is designed for easy extraction and insertion.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What kind of locking mechanism does the C4 Naifu S have?

Answer of Generated by AI and verified

This knife features a reliable locking system between the knife and its sheath. This design ensures the knife is held securely while also allowing for easy extraction and insertion when needed.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What type of blade does the C4 Naifu S knife have?

Answer of Generated by AI and verified

The C4 Naifu S is equipped with a straight edge blade that has a pointed tip. The blade is machined to create a razor cutting edge to enhance its cutting and penetrating effect.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

Does the blade of the Naifu S have any special features?

Answer of Generated by AI and verified

Yes, the blade incorporates a shaft remover. Additionally, a feature comes out from the bottom of the blade that can be used as a light hammer.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

How much does the C4 Naifu S knife weigh?

Answer of Generated by AI and verified

The product weight of the C4 Naifu S knife is 300g.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What is the handle of the C4 Naifu S made from?

Answer of Generated by AI and verified

The handle is made from plastic, specifically a recyclable POM material which is very sturdy and has low water absorption.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

What is the recommended use for the C4 Naifu S knife?

Answer of Generated by AI and verified

The C4 Naifu S knife is specifically recommended for spear fishing. Its compact and lightweight design makes it suitable as a primary or spare safety knife for divers.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

How can I carry the C4 Naifu S knife while diving?

Answer of Generated by AI and verified

The knife is designed for arm or weight belt mounting, providing easy and secure access. It comes with two rubber straps with stainless steel buckles for attachment.

* Generated by AI based on customer and product data

2026-09-13

Generated by AI and verified

C4 Naifu S knife

Is this knife suitable for adults?

Answer of Generated by AI and verified

Yes, the C4 Naifu S knife is designed for the adult age group.

* Generated by AI based on customer and product data

Ask a technical question about this product

Frequently bought together
Best sellers

Use cases

Spearfishing 100% Fit

As a reliable upgrade for regular spearfishers, this knife is explicitly recommended for the activity. Its pointed blade tip is effective for dispatching catches, while the straight, sharp edge handles cutting tasks with solid performance. The compact design allows for unobtrusive mounting on an arm or weight belt, keeping it accessible yet secure.

recommended_use: Spear Fishing,blade_tip_type: pointed,mounting: arm or weight belt,locking_mechanism: locking

Safety and Emergency Cutting 90% Fit

For divers needing a reliable safety tool, this knife offers balanced performance. The secure locking mechanism and sheath prevent accidental loss, ensuring the knife is there when you need it to cut away entanglements like fishing lines or nets. Its ergonomic design and easy one-handed extraction provide quick access in critical situations.

safety_lock: yes,locking_mechanism: locking,ergonomic_design: yes,sheath_included: yes

General Utility Diving Tool 80% Fit

This knife serves as a great all-rounder for various underwater tasks. The durable POM handle and sheath offer good resistance to the marine environment, while the sharp, straight edge is versatile for cutting ropes or other materials. Its compact size makes it a convenient tool to carry on any dive without being cumbersome.

material: POM,cutting_edge_type: straight,mounting: arm or weight belt,ergonomic_design: yes

Underwater Exploration and Investigation 70% Fit

For divers who explore wrecks or reefs, this knife is a useful tool for investigation. The pointed tip can be used for probing or pointing out marine life and features without causing damage. It's a solid, reliable tool for interacting with the underwater environment in a controlled manner.

blade_tip_type: pointed,handle_material: plastic,ergonomic_design: yes

Best for

Best for the Safety-Conscious Diver

This knife offers peace of mind with its reliable locking mechanism and dedicated safety lock, ensuring it stays securely in its sheath until needed.

Safety lock: yes, Locking mechanism: locking

Ideal for Spearfishing & Active Diving

Its compact design, versatile mounting options for arm or weight belt, and sharp, pointed blade make it a great all-rounder for underwater tasks.

Mounting: arm or weight belt, Blade tip type: pointed, Recommended use: Spear Fishing

A Solid Upgrade for Regular Divers

With its high scores for cutting efficiency, durable POM construction, and ergonomic design, this knife provides a noticeable improvement in quality and ease of use.

Ergonomic design: yes

Great for Divers Valuing Portability

This knife's compact and lightweight profile, combined with its secure mounting system, makes it an unobtrusive yet highly effective tool for any dive.

Product weight: 240g

Benefits

FunctionalConveniently Carry on Arm or Belt

Designed for minimal interference with your gear, this compact knife offers versatile carrying options. It can be easily mounted on your arm or weight belt, ensuring it's always within reach without being cumbersome during your underwater explorations.

Mounting: arm or weight belt

FunctionalErgonomically Designed for a Confident Grip

Experience superior handling and control thanks to the knife's ergonomic design. The handle is crafted to fit comfortably in your hand, providing a secure grip for precise movements, which is especially important in demanding underwater situations.

Ergonomic design: yes

FunctionalDurable and Effective for Spearfishing

Built for the specific demands of spearfishing, this knife features a straight cutting edge and a pointed tip for effective cutting and penetration. The handle and sheath are made from durable POM material, ensuring longevity and reliable performance dive after dive.

Recommended use: Spear Fishing

Cutting edge type: straight

Blade tip type: pointed

Material: POM

Ideal buyer profiles

The Safety-Focused Diver

This diver prioritizes reliability and security above all else. They need equipment that is dependable in critical situations and easy to operate under pressure, ensuring every dive is as safe as possible.

The C4 Naifu S is an excellent choice due to its dedicated safety features. It includes a reliable locking mechanism and a safety lock to ensure the knife stays securely in its sheath until needed. The sturdy construction, with the blade inserted fully into the handle, provides confidence and reliability for any underwater situation.

The Spearfishing Specialist

Focused on the specific demands of spearfishing, this user requires a compact, efficient, and easily accessible tool. Their gear must be lightweight and unobtrusive, allowing for maximum freedom of movement while providing effective cutting power when required.

With a pointed blade tip and a straight cutting edge, this knife is specifically recommended for spearfishing. Its compact and lightweight design is ideal for mounting on an arm or weight belt, ensuring it's always within reach without hindering movement. The ergonomic handle and simple locking system allow for quick, one-handed operation.

The Casual Diver

This individual enjoys recreational diving and snorkeling and looks for gear that is practical, durable, and easy to manage. They value portability and straightforward functionality over complex features, seeking a reliable tool for general underwater use.

The Naifu S is a great fit for the casual diver. Its compact size and 240g weight make it highly portable and easy to carry on an arm or belt. The handle and sheath are made from POM, a material with low water absorption, contributing to its durability and ease of care. The simple, effective locking mechanism ensures it's easy to handle during recreational dives.

Competitive features

Where it excels

Consider alternatives if...

Verdict

Specs comparison

Specs vs competitors
Similar alternatives to this product
Related products viewed by other shoppers
We think you might be interested in this

You might also be interested in

Tradeinn works with its own stock and with more than 2,000 suppliers connected daily. We update availability in real time to offer you the widest possible catalog, always at the best price. Some products may require additional delivery time depending on supplier availability.

Quick & easy 30-day return

Secure & safe shopping

100% Satisfaction Guaranteed

Always the best online price

Loading image
ai_chat

Have a question? We’ll help you right away.

You are interacting with a generative AI. By continuing, you accept the Legal Notice and confirm that you understand the Privacy Policy and Cookies Policy.

Chat

Have any questions?

Talk to an expert

WhatsApp

WhatsApp

+34 663 922 716
chat

Download our app

4.7

4.7 - +13K reviews

+13K reviews

Turn on notifications to instantly receive all the information about your orders!

Apple Store Google Play

Follow us on

Instagram diveinn YouTube diveinn Lab diveinn

About Tradeinn cerrar menu

Our customers’ reviews

Shop with confidence cerrar menu

Customer service cerrar menu

Other shops cerrar menu

Sustainable delivery

Our triathlon club

Departments

Top Brands

cerrar menu

Paypal Visa Mastercard Apple Pay American Express Revolut Adyen VerySign Netrivals Confianza online Geotrust Security Payment Klarna
tradeinn

Copyright 2009 - 2026 by diveinn. TRADEINN RETAIL SERVICES, S.L. CIF/VAT ES-B-17527524, C/ Pirineus, 9, 17460 Celrà (Girona), Spain. Terms & Conditions | Cookies policy | Privacy policy | Exercise the right of withdrawal | Legal notice | Privacy policy social networks | Internal information system