Made of chrome vanadium steel with long life and durability in use. Solid inner hex socket without magnet. This screwdriver bit set fits most corded or cordless drills for hex head screws. 9mm, 10mm, 11mm, 12mm, 13mm. Many applications. Suitable for home DIY, woodworking, auto parts, professional machine repair, etc. This is a set of 4 durable reducing and increasing adapters. Heavy-duty chrome-vanadium steel construction is designed for use with ratchets. A black oxide finish makes each part corrosion resistant and very durable. Spring-loaded ball stop keeps your sockets stationary and secure. There are a range of sizes to fit many socket or wrench combinations, including 1/2'(M)--3/8'(F), 3/8'(M)--1/4 '(F), 3/8'(M)--1/2'(F) and 1/4'(M)--3/8'(F).Specifications:-Material: chrome vanadium steel-Finish surface: electroplating, blackening - Hardness: 45 2 (HRC) - Color: black - Size: 1/2& 34; (male) - 3/8& 34; 34;(female)3/8'(male) - 1/4'(female)3/8'(male) - 1/2'(female)1/4'(male) - 3/8'(female) Package Content: 1 x 4pcs Adapter Set