Thread Size = No. 10, No. 4, No. 6, No. 8 Head Shape = Flat, Round Drive 타입 = Slot Material = Brass Countersunk ; Round Head Screws. Kits of countersunk and roundhead screws in various lengths Supplied in moulded plastic storage cases Screws are of the twin-threaded type Available with either Slotted or Cross recess heads