This product is the Replacement Blade Cartridge for the UST-540 and is also compatible with the Universal Cable Stripping Tools (UST-500 series) and Coaxial Cable Stripping Tools (UST-100 series). This blade cartridge features the following:

Provides a 2-level strip for RG59 and RG6 COAX Cables for F, BNC, and RCA connector termination
High carbon steel blades last for over 5,000 strips
Cartridge is reversible for ambidextrous use
Cable stop on one side of the cartridge ensures precise stripping without need to make adjustments