Wilwood’s unique Thermlock® T1 Short Track Pistons is an optional feature on our Billet Dynalite calipers. The pistons incorporate a stainless steel shield and coated aluminum shell configuration to provide a highly efficient thermal barrier between the brake pads and the caliper body, seals, and fluid. Lower operating temperatures eliminate seal crystallization and localized fluid boiling while providing longer caliper service life through decreased distortion in the caliper body and piston bores.