Specifications: It is made of high quality materials, which has high hardness, good toughness, rust protection and good anti-corrosion. This square bit socket set is perfect for use with breaker bars, torque wrenches, and ratchets. With mini size, it is lightweight, which is easy to carry. Item Name: Spline Bit Sockets Material: Chrome Vanadium Steel Quantity: 10Pcs/Set Features: Durable, Lightweight, Rustproof, Anti-Corrosion 12 Point Spline Bit: Bit M4/M5/M6 Square Bit Size: 1/4" (6.35mm), Length: 37mm/1.5" (Approx.) Bit M8/M9/M10/M12 Square Bit Size: 3/8" (10mm), Length: 48mm/1.9" (Approx.) 12 Point Middle Hole Bit: Bit M14 Square Bit Size: 3/8" (10mm), Length: 48mm/1.9" (Approx.) Bit MT6/M18 Square Bit Size: 1/2" (12.6mm), Length: 55mm/2.2" (Approx.) Notes: Due to the light and screen setting difference, the items color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 10 x Spline Bit Sockets