This Compressor easily compresses most Macstrut springs and allows for repair on strut tubes, bent struts and other damaged pieces Compress coil springs to repair or replace MacPherson struts, shock absorbers and spring sets Builtin detent safety pins and broad spring contact securely locks into place for protection Universally compatible with struts assembly that remove from the vehicle to transfer the old spring on the new strut Acme threaded rod allows for durable and smooth compression of springs both on or off the vehicle with hand or power tools Constructed with forged hooks and center screw hardened for maximum strength and longevity