> 1) Ductile iron Handle, or malleable cast iron.
> 2) The adjustable/mobile jaw with high quality 45# Carbon Cast Steel /Drop forged steel, 45#
> The fix  jaw: cast iron, 60#(heat treatment with quench and tempering ,jaw teeth induction quenched
> 3) The nut: 45# Carbon Cast Steel /45#  Drop forged steel
   4)size:8" 10" 12" 14" 18" 24" 36" 48"