Lowes offers TOUGHBUILT Carbide Bi-metal Utility Razor Blade 50 -Pack for $9.98 (reg. ) with free shipping. 

Product Description:
ToughBuilt 50-Pack Carbide Replacement Blades provide longer-lasting sharpness for consistent cutting performance. A shatterproof bimetal blade with a carbide edge is designed to fit all ToughBuilt utility knives (including Scraper Utility Knife, TB-H4-01) and most standard utility knives. Ideal for use with shingles, plastics, and sheet materials, these blades excel in a variety of applications. The blade container not only holds your blades securely but also features a convenient blade dispenser that opens like a drawer to keep the fresh blade at the ready. Plus, the discarded blades can be neatly stacked in the top compartment for safe disposal. Never compromise on the quality of your cuts and enhance your cutting experience with the ToughBuilt 50 pc Carbide Universal Utility Replacement Blades.