-EQUIPPED BITS SIZE - 20 piece hex driver/hex drill precise bits in the following sizes: 10 pieces in SAE of 5/64 inch, 3/32 inch, 7/64 inch, 1/8 inch, 9/64 inch, 5/32 inch, 3/16 inch, 7/32 inch, 1/4 inch, 5/16 inch, and 10 pieces in Metric of 1.5mm, 2mm, 2.5mm, 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm. INDUSTRIAL GRADE QUALITY - The hex drill bits are made from S2 steel with a rust-resistant finish, featuring labeled size marks & magnetic tips. Two portable rubble strips in a durable plastic case: one organizes bits in SAE, the other in Metric. EXPERIMENT TESTS - The bits have undergone torsion and hardness tests. Results indicate that the maximum torsion force of the bits is 180-200N and their hardness ranges from 57-59HRC. High torsion capability and appropriate hardness help prevent bit wear. USAGE VERSATILITY - 1/4 inch quick release hex driver bits are suitable for electric screwdrivers, hand screwdrivers, electric drills & air drills. Ideal for working on vehicles, bicycles & furniture, and for assembling/repairing your furniture. colour: silver Material: alloy steel Package Contents: 20 x hex driver Only the above package content; other products are not included. Note: Light and different displays may cause the color of the item to differ slightly from the actual product. The measurement allowed error is +/- 1-3cm.