earth clamp 1>Jaw is iron with chromium 2>Interior braid is copper 3>jaw pads is brass,iron with copper,iron with zinc American Type 500A earth clampSpring loaded Earth Clamps feature copper braid between brass jaw pads for optimum conductivity. Strong spring pressure, available in different amperages.1>Jaw is iron with chromium2>Interior braid is copper3>jaw pads is brass,iron with copper,iron ...