1. Material: vanadium steel 2. Standard: formula 3. Size: about 25x12x4.5 cm/set 4. Weight: about 843g/set 5. Scope of application: auto repair and mechanical repair 6. Features: beautiful and practical, not easy to rust, durable, high hardness, large torque, good toughness, wide applicability 7. Description: use with 3/8 inch wrench 8. Contains: one long sleeve, one short sleeve and one small open sleeve