A Square Bit Is A System Used To Turn A Screw. At A Minimum; It Is A Set Of Shaped Cavities And Protrusions On The Screw Head That Allows Torque To Be Applied To It. Usually It Also Involves A Mating Tool; Such As A Screwdriver That Is Used To Turn It. The Nr 2 Size Bit Is Suitable For Use With Screw Sizes Of 4.0mm 5.0mm
