Erbauer Mixed Screwdriver bit, 32 pieces These Erbauer screwdriver bit are made from steel (s2 grade). ---Drive type - Mixed ---Material - Steel (S2 grade) Features & Benefits ---Geometrically designed precision tip that fits into fasteners more precisely, reducing stripping and cam-out ---Made from cold-forged high-grade steel that makes this a heavy-duty product, capable to withstand high