This collet body is made of copper. In addition, it is designed for applications including non-gas lens. Plus, it is compatible with 20, 20H-320, 20P, 9, A-125, HW-20, HW-25, HW-9, PTA-9, PTW-20, W-200, W-225, W-250, W-280, W-310, W-375, 20, 20F, 20H-320-25R, and more, Weldcraft brand and is for use with A-125 Series, A-80 Series, W-200, W-250 Series, A-150 Auto, W-250 Auto, W-280, W-375.