Engineered for electricians, these screwdriver bits are crafted from high hardness alloy steel ( HRC63°) with anti rust phosphating, ensuring durability and secure screw grip Color coded shafts and length ( 65mm / 110mm) in FPH / series ( 4.5 7mm) enable quick identification and compatibility with various electrical fastening tasks The three piece set covers multiple screw head sizes with enhanced retention, streamlining electrical projects while reducing tool change frequency in confined workspaces Ideal for professional electricians, maintenance technicians, and enthusiasts requiring tools for electrical panel installations or appliance repairs for wiring adjustments, circuit breakers installations, and other scenarios demanding rust resistant, screwdriver bits that prevents fastener drops, Manufacturer: RGYBAO