These replacement bits work with Klein's HVAC 8-in-1 Slide Driver screwdriver/nut driver (32596) and 11-in-1 multi-bit screwdriver (Cat. No. 32527). The double-ended Schrader Valve Core tool and 1/8" (3.2 mm) slotted bits are designed for precision work. Made of the highest quality tempered steel, carefully heat-treated for maximum strength, and precision milled to fit screw openings securely.