1. Stainless Steel Retractable Utility Knife - Premium Self Loading Heavy Duty Carpet, Rope, Cardboard, Box Cutter Knives, 5 Sharp Rust Proof Razor Snap Off Blades - Metal Safety Lock, Comfortable Handle (Click Link to Check Price on Amazon)
Editor's Rating : 8.8 out of 10
★ SAFE & SECURE - This Self-Loading utility knife contains a safety auto headlock to ensure your safety and control from accidents while it is not in use it comes with 5 blades that are hidden in the chamber

2. MulWark Premium Rust-Proof Stainless Steel Snap-Off Utility Knife Multi Box Cutter For Rope, Cardboard-5pc Extra Sharp Quick Change Razor Blades Self-Loaded, Metal Safety Lock And Rubber Handle (Click Link to Check Price on Amazon)
Editor's Rating : 8.9 out of 10
SUPREME CUTTING PERFORMANCE - The self-loading 5pc 18mm rust resistant retractable snap blades are all made of SK4 steel, featuring triple ground cutting edge, sharper and can stay sharp longer than normal ones, with the headlock ensuring strong and stable cut while usingCONVENIENT BLADE CARTRIDGE - Can store up to 6 breakaway blades in the chamber, keep you hassle free from frequent blade replacement

3. Slice 10514 Mini Cutter, Ceramic Safety Blade, Pocket Sized, Auto-Retractable, Stays Sharp Up to 10X Longer (Click Link to Check Price on Amazon)
Editor's Rating : 9.6 out of 10
Auto-retractable for extra safetyIncludes one double-sided Slice ceramic blade

4. PenBlade - Stainless Steel Craft Knives - 3 Pack - Craft, Hobby, and Utility Knife with Retractable Blade for Safety - Includes Three Blade Sizes #10, #11A, and #15 (Click Link to Check Price on Amazon)
Editor's Rating : 8.8 out of 10
New to PenBlade? Check out our Try Two offer. Two PenBlades for $6.99. Surgical grade stainless steel blades for long lasting sharpness & durability. Not carbon steel that dulls and breaks easily.Push button blade retraction for instant safety and storage. No caps necessary.

5. 10 Pack Utility Knife Blades- 2 3/8 X 3/4 X 2 3/8 Inch Edge- For All Standard Utility Knife Handles- For All General Purposes, Cutting Boxes, Plywood, Leather, Plastic, And Sheetrock. - By Katzco (Click Link to Check Price on Amazon)
Editor's Rating : 9.3 out of 10
MATERIAL- Steel backed, high carbon steel blade fits all standard razor blade tools makes it the perfect item to cut any surface.11 PACK VALUE- with 10 single edge razor blades in this package you will not ran out of stock so soon.