Classical

Classical

The socket-headed Robertson screws are self-centering, reduce cam out, stop a power tool when set, and can be removed if painted-over or old and rusty.[11] In industry, they speed up production and reduce product damage. One of their first major industrial uses was the Ford Motor Company's Model A & Model T production. Henry Ford found them highly reliable and saved considerable production time, but when he couldn't secure licensing for them in the United States, limited their production use to his Canadian division. Robertson-head screwdrivers are available in a standard range of tip-sizes, from 1.77mm to 4.85mm. Reed and Prince, also called Frearson, is another historic cross-head screw configuration. The cross in the screw head is sharper and less rounded than a Phillips, and the bit has 45° flukes and a sharper, pointed end. Also, the Phillips screw slot is not as deep as the Reed and Prince slot.[12][13][14] In theory, different size R&P screws fit any R&P bit size.[15]

Pozidriv and the related Supadriv are widely used in Europe and most of the Far East.[16] While Pozidriv screws have cross heads like Phillips and are sometimes thought effectively the same, the Pozidriv design allows higher torque application than Phillips. It is often claimed that they can apply more torque than any of the other commonly used cross-head screwdriver systems, due to a complex fluting (mating) configuration.

Japanese Industrial Standard (JIS) cross-head screwdrivers are still another standard, often inaccurately referred to as Japanese Phillips. Compatible screw heads are usually identifiable by a single depressed dot or an "X" to one side of the cross slot. This is a screw standard throughout the Asia market and Japanese imports. The driver has a 57° point with a flat tip.[17]

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