D4*60*D2.5*20*1# Ø4 wing-type round shank screwdriver bit, length 60mm, stepped down to Ø2.5 length 20, 4-point tip size #1

D4*60*D2.5*20*1# 4mm wing-shank screwdriver bit, 60mm length, stepped down to 2.5mm diameter (20mm length), Phillips #1 tip

Used for torque-controlled electric screwdrivers.

S2 steel material