Sizes: U4, U5, U6, U7, U8. TECHNICAL DETAILS A set of 5 security bits designed for use on U-type, snake eye, 2-hole, or spanner type tamper proof screw heads. Manufactured from S2 silicon steel, with a magnetised tip, these 1/4" shank bits and magnetic holder are ideal for use with cordless screwdrivers fitted with a quick chuck, cordless drills and bit drivers.
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