The Unger ErgoTec Ninja SS Replacement Blades are a 25 pack of 4" stainless steel replacement blades in a compact, handy dispenser that safely stores new and used blades. These blades are dual-sided and made of rust-resistant 440A grade stainless steel for long use. Each blade is honed to a precise edge, creating a perfect cutting angle that is razor sharp and consistent. Use these blades as a replacement in the following scraper: 4" Ninja Adjustable Scraper (EN100) Unger Part No. ENB10