Universal olfa knife 18mm with reinforced guide + sharp SK5 blade
Are you looking for a reliable, extremely sharp and durable tool for everyday creation, home renovation or professional use in the workshop? The OLFA 18mm universal knife with reinforced guide and black SK5 blade (SKU: G01849) is the perfect choice for anyone who demands precision, safety and a long tool life at work. This top technical knife combines an ergonomic design with exceptional cutting power, allowing you to easily process a wide variety of materials.
Thanks to its advanced black SK5 high-carbon steel blade and robust metal guide, this olfa knife provides the stability you need for more demanding tasks. Forget about blade twisting and imprecise cuts - with the reinforced guide, every cut will be straight, clean and safe.
Why choose the universal olfa knife with SK5 blade?
Every craftsman knows that a quality blade is the key to successful work. This model stands out due to its thoughtful design, which combines safety features with top performance:

Exceptional sharpness with SK5 steel: The blade is made of premium SK5 carbon steel, which is known for its hardness and long-lasting sharpness. The black anti-corrosion coating further protects the blade from rust and external influences, extending its lifespan.
Reinforced metal guide: The metal guide prevents the blade from bending and wobbling while you work. This allows you to apply more pressure and achieve extreme precision even when cutting harder materials.
Ergonomic and non-slip handle: The profiled handle is coated with high-quality non-slip rubber, which ensures a firm and comfortable grip. Even during long-term work or sweaty hands, the knife will not slip out of your hand, which significantly reduces the risk of injury.
Easy blade break: When the tip of the blade wears out after prolonged use, simply break it off and you have a perfectly sharp blade again to continue working.

Versatile use in the workshop and at home
This universal olfa knife 18mm is an indispensable tool for a wide range of tasks. Due to its robustness and sharpness, it is ideal for:

Precise cutting of wallpaper and foils when painting or decorating.
Quickly open packages, cut cardboard and adhesive tapes.
Cutting thicker materials such as carpets, linoleum and floor coverings.
Trimming cables, plastic and other materials during installation work.

Technical specifications and features
Before purchasing, check the key technical features that confirm the quality of this professional tool:

Blade width: 18 mm
Blade material: High quality SK5 carbon steel with black anti-corrosion coating
Blade type: Sliding, broken blade
Blade guide: Robust metal guide for maximum stability
Housing and handle: Durable plastic, profiled handle coated with non-slip rubber
Product code (SKU): G01849
Category: Blades and knives

Instructions for safe use
Although the knife is designed with maximum safety in mind, it is an extremely sharp tool. When working, always make sure to move the blade out of the guide only as far as is absolutely necessary for the cut. When breaking off a worn part of the blade, always use safety glasses and the dedicated slot at the back of the knife or pliers. When finished, pull the blade completely back into the housing.
Frequently Asked Questions (FAQ)
What does the SK5 blade designation mean?
SK5 is a high-quality Japanese carbon steel that is often used to make blades, saws, and other cutting tools. It is characterized by its exceptional hardness, wear resistance, and ability to maintain sharpness for a long time. The black coating on this blade further prevents corrosion and reduces friction when cutting.
Can the blade in this knife be replaced when it wears out?
Of course. Once you have used up all the breakable parts of the blade, you can simply open the knife and insert a new standard 18 mm replacement blade. The metal guide makes the housing extremely durable and suitable for long-term repeated use.
Is this knife suitable for cutting thicker carpets?
Yes, thanks to the reinforced metal guide that prevents the blade from twisting and the extremely sharp SK5 steel, this knife is also great for more demanding tasks, such as cutting carpet, thicker cardboard, and other harder materials.


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:
• Check the 18 mm blade, metal guide, slide and blade lock before use.
• Move the blade outward only as far as necessary to make the cut.
• Use the slider to set the desired blade length and lock it to prevent it from moving while cutting. The model has an 18 mm SK5 blade and lock.
• Place the material on a stable surface and secure it if possible.
• Hold the knife with a firm grip and cut away from your body and fingers.
• For thicker material, it is better to make several shallow cuts than one with great force.
• It is suitable for cutting wallpaper, cardboard, tape, carpets and lighter materials.
• After finishing work, retract the blade completely into the handle and lock it.
Changing the blade
• Fully retract the blade and secure the knife against unintentional movement.
• Release the lock or change mechanism.
• Carefully remove the old blade.
• Insert the new 18 mm SK5 snap-off blade into the guide.
• Check that it is correctly installed and moves smoothly.
• Lock it again before use. The blade is made of SK5 carbon steel with an anti-corrosion coating.

Useful tips for work:
• Reinforced metal guide ensures better blade stability when cutting.
• Rubberized profiled handle provides better grip.
• When the blade tip becomes blunt, use a breakaway segment according to the blade design or replace it.
• Do not use this utility knife as a substitute for an electrician's knife to cut electrical wires.

Warnings:
• CAUTION – the blade is very sharp.
• Always cut away from your body and hands.
• Before cutting, check that there are no electrical cables, pipes or other hidden obstacles behind the material.
• Do not use a damaged or loose blade.
• Do not subject the blade to lateral forces as it may break.
• When changing or breaking the blade, use protective gloves and be careful of broken segments.
• Always close the knife completely after use or retract the blade and keep it out of the reach of children.

Same summary

The 18mm universal olfa knife with a reinforced guide and a sharp SK5 blade is a practical choice for users who often perform various home or craft tasks - from cutting packaging and cardboard to working with plastic or lighter construction materials. Due to the robust design of the guide and the possibility of quick blade changes, it is also suitable for more intensive tasks, where a combination of durability and ease of maintenance is important. For more specialized work or processing electrical conductors, it is recommended to use dedicated knives, as the universal versions do not have adequate protection or technical features for such use. The compromise is that the shorter blade allows greater control and safety in detailed work, but is slightly less suitable for thicker and very coarse materials.

Recommendation source: Enaa guides and team experiences.

User view

This universal olfa knife is popular among home craftsmen, creative people and anyone who wants to cut various materials quickly and reliably - both in the workshop and around the house or in the field. It is used by those who value a sense of control when cutting and easy blade changes without complicated procedures. In everyday situations, it is most often used when unpacking packages, arranging insulation material, preparing building elements or in modeling projects.

Users often choose Geko brand tools, as their range is known for its good reliability and robustness, which is especially important for intensive or regular use.

Why buy at Enaa

At Enaa you will find a comprehensive range of knives and blades, clearly presented with useful filters to make it easier to choose the right tool. Our team regularly updates the category with new products so you can always compare the latest products in one place.

Answers to frequently asked questions

What materials is this olfa knife best suited for?

The knife is designed for cutting paper, cardboard, plastic, foil and small pieces of rubber or thin cardboard. For thicker or very hard materials, it is recommended to use a more robust or specialized knife.

Can the blade be quickly replaced?

Yes, the blade of this model is designed to be replaced easily and without the use of additional tools, which makes maintenance easier in everyday use.

What is the safety when storing and carrying a knife?

The knife has a blade locking mechanism, which provides greater security when folded. We recommend that you always close or lock it when carrying it.

Is the knife also suitable for precise modeling work?

The shorter blade length allows for good control during detailed cuts, making it suitable for basic creative and modeling tasks, but for extremely fine materials, a specialized, thinner cutter may be more suitable.

What do I do if the blade becomes dull?

We recommend replacing the blade as soon as possible – SK5 replacement blades are available and easy to insert.

Description updated: April 2026