Collar screw 3780220 with 1/4 inches hexagonal and PH2 recess, dimensions 4.2 x 25 mm (set of 100) Twin thread. Fully threaded Suitable for plug, sheet steel and wood fibreboard Material: Hardened, electroplated steel Works well together with magnetic sockets TST-V 9x100 and TST-V 10x45, and long Phillips bits PH 2x110, in confined spaces