Universal olfa knife 18mm with reinforced guide - Professional upholstery knife for precise cuts
Are you looking for a reliable, durable and affordable tool for precise cutting of various materials? The olfa universal knife 18mm with reinforced guide (SKU: G01841) represents the perfect synergy between lightness and extreme stability. This indispensable tool is designed for professional craftsmen, installers and upholsterers as well as for DIYers who demand uncompromising precision in their work. Forget about wobbly cuts and unstable blades - with the reinforced metal guide, every cut will be made safely, quickly and perfectly straight.
Due to its exceptional versatility, this 18 mm upholstery knife is an ideal choice for cutting cardboard, wallpaper, leather, carpets, packaging film and other materials. The ergonomic design of the housing provides excellent grip and optimal control over the cut, which reduces hand fatigue even during prolonged work. For only €2.99 you will receive a top-quality tool from the Blades and Knives category, which will become an indispensable part of your workshop, office or home tool drawer.
Why is a reinforced metal guide the key to success?
When working with sharp blades, safety is always a top priority. Most standard plastic blades bend or twist under high pressure, which can lead to unwanted material damage or even dangerous cuts. Our universal olfa knife solves this problem with a built-in reinforced metal guide. This robust guide holds the 18 mm blade firmly in place, preventing any wobble or movement of the blade during work. The result is perfectly even pressure on the workpiece and exceptional precision with every stroke.
In addition to its superior stability, this knife is extremely easy to maintain. When the blade wears out, you don't have to look for additional tools or waste valuable time to change it. The innovative design allows you to replace the worn blade completely manually and in just a few seconds through the tail of the knife. This allows you to continue working without interruption and maximize productivity on every project.
Key features and technical advantages

Reinforced metal guide: Ensures maximum structural stability of the blade, prevents bending under pressure and enables safe and precise cutting of even more demanding and harder materials.
High-quality plastic housing: The ergonomically designed housing is extremely light to carry, yet robust enough to withstand the daily rigors of the workshop or in the field.
Standard blade width 18 mm: The knife is fully compatible with a wide range of standard replacement snap-off blades that can be quickly and easily found on the market.
Quick manual blade change: Changing a worn blade is done quickly and easily through the back (tail) of the knife, without the need for screwdrivers or other tools.
Versatile use in practice: An excellent tool for precise cutting of paper, cardboard, foil, wallpaper, carpets, leather and other filling materials.
Exceptional value for money: Professional functionality, durability, and security are available to you at an extremely affordable price of only €2.99.

Advantages of using an olf knife in everyday practice
Using this professional tool brings numerous practical advantages that you will feel from the first cut:

Increased safety at work: Since the metal guide prevents the blade from twisting, the chance of the blade jumping out of the cut line and causing injury is minimized.
Faster workflow: Quick and easy blade changes through the back of the knife mean fewer interruptions and faster completion of your projects.
Long tool life: The combination of a durable plastic housing and an internal metal core ensures that this knife will remain part of your standard equipment for a long time.
Perfect precision: The stability of the blade allows for straight, clean and precise cuts, which is crucial for tasks such as wallpapering or precise cutting of materials.

Instructions for safe use and easy maintenance
To ensure a long life of the knife and maximum safety at work, we recommend that you safely retract the blade into the housing after each use. When you notice that the blade is losing its original sharpness, simply break off the top part using pliers or the dedicated attachment at the end of the knife. When you have used up the entire length, simply insert a new 18 mm blade through the tail of the knife. Due to the simple and proven mechanism, this process is completely safe, fast and does not require any prior knowledge.
Frequently Asked Questions (FAQ)
How do I change the blade on this olfa knife?
Changing the blade is extremely simple, fast and safe. It is done completely manually, without the use of any additional tools. You simply pull out the used blade through the back (tail) of the knife and insert a new 18 mm wide replacement blade through the same opening.
Is this knife suitable for more demanding tasks and thicker materials?
Yes. Thanks to the integrated reinforced metal guide inside the plastic housing, this knife is significantly more stable and durable than conventional, all-plastic models. It is easily suitable for cutting thicker materials such as multi-layer cardboard, wallpaper, carpets and thinner plastics.
What replacement blades are compatible with this model?
This universal olfa knife uses standard 18mm snap-off blades. This is the most common blade format on the market, meaning that you will be able to easily find and purchase replacement consumables anywhere.


Responsible persons:
GEKO - GEKO SPÓŁKA Z OGRANICZNĄ ODPOWIEDZIALNOŚCIA SPÓŁKA KOMANDYTOWA, ul. Spacerowa 3, 97-500 Kietlin, Poland, (+48) 446824004, geko@geko.pl
Distributor for Slovenia: Haloorodje.si, Online Sales, Rok Groznik sp, Podturn 42, 8350 Dolenjske Toplice, info@haloorodje.si, +38669731944, Slovenia
Product origin: China

Instructions for using the product:
• Pull the blade out as far as necessary to cut safely.
• Lock the blade in the desired position with the locking mechanism.
• Place the material on a stable surface and secure it well while cutting.
• Guide the knife away from your body and use even pressure.
• After use, push the blade back into the housing and store the knife in a safe place.

Useful tips for work:
• For a more precise cut, use the sharp part of the blade and do not apply unnecessary pressure.
• When the blade becomes dull, replace it or break off the worn segment if the knife is designed for this.
• Reinforced guide helps guide the blade more stably during more demanding cutting.
• For a straighter cut, use a ruler or other suitable guide.
• Remove any remaining material from the knife after use.

Warnings:
• The blade is very sharp – handle it with care.
• Always cut away from your body and hands.
• Do not use a damaged blade or guide.
• Be especially careful when changing the blade and follow the manufacturer's instructions.
• Store the knife with the blade in the closed position and out of the reach of children.

Same summary

The olfa 18mm universal knife with reinforced guide is suitable for household users, DIYers and anyone who often performs typical cutting tasks - such as opening packaging, occasional construction work or project work with various materials. The product offers a good balance between practicality and robustness, which is especially useful for frequent or more demanding use. Due to the 18mm blade, it is less suitable for very precise work or for working with thicker and harder materials, where the length or thickness of the blade limits its capabilities. The reinforced guide offers greater durability, which makes it easier to use in more intensive work.

Recommendation source: Enaa guides and team experiences.

User view

This type of universal knife is most often used by home users for a variety of tasks - from cutting cardboard, wallpaper or plastic, to quickly preparing material for minor repairs. It is also popular in workshops, where a reliable and sufficiently robust knife comes in handy for precise, but not very demanding tasks. Due to the reinforced guide, it is suitable for those who value a longer tool life and are looking for a balance between power and blade control.

Users also choose the Geko brand because of its reputation for practical tools for everyday and professional use.

Why buy at Enaa

On Enaa you can quickly compare different knife models, and with detailed descriptions it is easier to check whether the blade type and construction meet your needs. In case of additional questions, the team of experts is available for practical advice on choosing a tool from the Knives and Blades category.

Answers to frequently asked questions

For which materials is this olfa knife particularly suitable?

The 18mm universal olfa knife with reinforced guide is useful for cardboard, paper, thin plastics and rubber, as well as for wallpaper and light construction work where a longer blade or maximum cutting power is not required.

Is the blade easy to replace?

Yes, in this model, changing the blade is simple, allowing for quick sharpening without complicated procedures.

Is the knife also suitable for more demanding construction work?

For thicker materials or intensive construction tasks, it makes sense to check out models with an extended blade or an additionally reinforced design, as the 18mm blade primarily provides stability and control for medium-duty tasks.

How safe is it to use this knife?

The knife has a stable, reinforced guide and an ergonomically designed handle that helps provide better grip and control. However, as with all sharp tools, caution is recommended when using and storing them.

Why do users choose the Geko brand?

The Geko brand is known for its balance between price, durability, and reliability, which is often sought after by both home craftsmen and regular tool users.

Description updated: April 2026