Line pressing are used by the terminal box, the impact on the contact force is bigger, before we will screw, wire frame with threaded surface of the tongue will then bounce, so the screw can appear the opposite effect, and because the temperature lead to lead change in the diameter, so basic it is offset by the effect of elastic directly, so do not need again to tighten the screw. Materials: t2 copper tube with more than 99.95% copper content plating: natural color standard packing details: product+ polybag + label + inner box + export carton + pallet product details.