This Sealey AK3846 Coil Spring Compressor is designed for safely compressing coil springs. It features carbon steel construction with hardened lead screws and cast jaws for durability. The wrap-around coil jaws ensure extra safety, and the long reach jaws are ideal for the longer coil springs found on modern vehicles. It operates with a 21mm Hex or 1/2"Sq drive and has a maximum jaw opening of 390mm. The maximum capacity per pair is 1000kg.