1Features: Precisely and automatically machined bit tips to ensure accurate size, chamfered bit ends insert smoothly into fasteners and protect both bits and fasteners from damaged edges. 2Application: To tighten and untighten high torque triple square screws and bolts commonly used in the alternator and pressure plate of cars. 3Performance: Sockets are made from heat treated chrome vanadium steel for strong strength and durability, stable and reliable performance. 4Portable Box: Spline tip bit socket set includes a sturdy plastic organizing case for secure storage and easy carrying. 5Reliable Material: Chrome vanadium steel and Abs material, high hardness that reduce wear outs and insure longevity.