Retractable Utility Knife vs Snap Blade Knife for Everyday Use
By Excel Blades: Precision Cutting Tools & Craft Knives | Published: 2026-10-18
Category: Comparisons
Compare the Excel Blades K870 retractable utility knife and K850 snap blade knife to decide which everyday cutting tool fits your needs.
Quick answer
Choose the K870 retractable utility knife for quick, safe package opening and pencil sharpening; pick the K850 snap blade knife for heavy-duty cutting where blade longevity matters most.
Safety vs. blade economy
The K870's retractable design and safety lock let you hide the blade between cuts, which reduces accidental nicks when reaching into a drawer or pocket. The K850 relies on a locking mechanism to hold the blade rigid during use, but the blade stays exposed when locked.
The K850's 18mm snap-off blade gives you eight fresh edges from one blade. You snap off the dull tip and continue working without changing the whole blade. The K870 uses a standard #92 carbon steel blade that you replace entirely when dull.
Grip and handling differences
Both knives have plastic bodies, but the K870 is built for lighter tasks and includes a safety lock that also prevents accidental retraction during use. The K850 is heavier and designed for sustained cutting on materials like cardboard, drywall, or plastic strapping.
Because the K850 uses an 18mm blade, it provides more leverage and a deeper cut per pass. The K870's smaller blade is better for controlled, short cuts and detail work like sharpening pencils.
Trade-offs at a glance
- Blade safety: K870 retractable design hides the blade between cuts; K850 blade stays exposed when locked.
- Blade longevity: K850 snap blade offers 8 edges per blade; K870 requires full blade replacement when dull.
- Cutting power: K850 18mm blade handles heavy materials; K870 #92 blade is better for light, controlled cuts.
- Versatility: K870 works for packages and pencil sharpening; K850 suits contractors, DIYers, and warehouse tasks.
Product facts
- K870 Retractable Plastic Utility Knife: The Excel Blades K870 Plastic Utility Knife features a retractable #92 carbon steel blade with a safety lock. You get a compact, safe tool for everyday tasks like opening packages and sharpening pencils without leaving a blade exposed.
K870 Retractable Plastic Utility Knife - K850 Heavy Duty Plastic Snap Blade Knife: The Excel Blades K850 Heavy Duty Plastic Snap Blade Knife uses an 18mm snap-off blade with 8 breakaway segments. Each blade gives you eight sharp edges, reducing the frequency of blade changes and lowering long-term costs for heavy cutting jobs.
K850 Heavy Duty Plastic Snap Blade Knife
Which one fits your routine?
Best for
- Home users who need a safe, retractable knife for occasional packages and pencil sharpening
- Crafters who want a compact tool with a safety lock for light cutting
Not for
- Heavy-duty cutting jobs that require a durable, long-lasting blade edge
