History of Robertson Screws

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by Fred Scheuler In 1906 Peter Lymburner Robertson, wounded by the slippery slot of the primitive screwnail, invented the square recess

Find Robertson Screw stock images in HD and millions of other royalty-free stock photos, illustrations and vectors in the Shutterstock collection  The square-head screw was invented by P I Robertson, a Canadian, in 1908 It offered a big advantage over the slotted screw head because

nascar slot car slotted or phillips, that stays in the newer screw heads slotted screwdrivers with them have you tried a Robertson screwdriver ?! The Jonard Tools 6-in-1 Multi-Bit Robertson Screwdriver eliminates the need for multiple tools in your belt This tool can be configured to 6 types of