What is hardware handles science group of head?

Metal polishing base has been implemented, address: AngYi fishing cross the village ( Wood group for land) Polishing machine number 800, now the relevant matters: - ->
hardware handles science group of first batch of head, usually refers to install hand electric drill or electric hammer above the screw with a screwdriver head. Of electric head is electric screwdriver to tighten or loosen the screw, belongs to a small electric tools.

when installed hardware handle batch of head is useful.