DURABLE: This 10 piece impact grade 50mm screwdriver bit set has a black oxide coating for durability. QUICK CHANGE: It has a quick change ¼" hex. shank for convenience. CORDED OR CORDLESS: The bit set can be used in both corded or cordless impact drivers for added versatility. Contents:50mm hex shank impact driver bits, 5 x PZ2, 3 x PZ3, 2 x PH2.