Diamond screw punch - VA an innovative splitting punch with three cutting tips: punching waste is split into three parts! Suitable for stainless steel (VA), sheet steel (ST 37), plastic and aluminum Operation: Manual and hydraulic (We recommend the use of hydraulics.) Design: Punch and die, tension screw with ball bearing. Hole diameter 30.5 mm, material thickness 3.5 mm, size 1-7/32', screw size 19.0x55.0 mm, pre-drill diameter 20.4*mm