Why use a tool This tool set enables convenient removal and installation of lock nuts and component mounting bolts that are often difficult to reach directly. When to use Nuts and bolts are typically hidden in the engine compartment, behind components, and often close to the radiator or other obstacles. To easily tighten or loosen automotive parts, this tool set enables efficient disassembly and installation while offering protection for repair personnel. Premium material The handle is made of 45# steel, and the remaining components are forged from chrome-molybdenum steel (Cr-Mo). These materials provide excellent hardness and strength, with good corrosion resistance, wear resistance, and high-temperature resistance. Package includes This belt pulley wrench set features a long curved handle for easy access and includes 13 interchangeable adapters, suitable for almost all types of vehicles. The adapters include: 5 x Torx: E10, E12, E14, E16, E18 and 8 x 12-point: 12, 13, 14, 15, 16, 17, 18, 19mm (0.47"-0.74"). Applications - Use for belt pulley and tensioner work in tight engine bays where space is limited. - Loosen or tighten lock nuts and mounting bolts hidden behind components near the radiator. - Suitable for a wide range of vehicles, including cars and light trucks, that use Torx and 12-point fasteners in belt drive areas.