Overview Slotted drives Cruciform drives Square drives Multiple-square drives Internal hex drives A screw drive is a system used to turn a screw. At a minimum, it is a set of shaped cavities and protrusions on the screw head that allows torque to be applied to it. Usually, it also involves a mating tool, such as a screwdriver, that is used to turn it. The following heads are categorized heremonality, with some of heremon drives being classified as tamper-resistant. heree in a range of sizes, typically distinguished by a number, such as Phillips #00. These sizes See more on here Text under CC-BY-SA license Robertson Robertson Inc https://www. robertsonscrew .com In 1908, P. L. Robertson began to manufacture a square recess impression in the head of a screw in Milton, Ontario, Canada. At that time, it was a revolutionary change in the fastener industry. The Robertson socket head screw soared in popularity. Craftsmen favored it because it was self-centering and could be driven with one hand. Industry came to rely on it for the way it reduced product damage and sped up production. Peter Lymburner Robertson (December 10, 1879 – September 28, 1951) was a Canadian inventor, industrialist, salesman, and philanthropist who popularized the square-socket drive for screws , often called the Robertson drive.Although a square-socket drive had been conceived decades before (having been patented in 1875 by one Allan Cummings of New York City, U.S. Patent 161,390),

Task Tools T50544 Number-2 Robertson Acetate Hard Grip Screwdriver , 1-1/2-Inch Stubby The Roberston screwdriver , also known as a square screwdriver , was invented in 1908 by P.L. Robertson , a native Canadian. The screwdriver presented a solution to the frequent problem users encountered with flathead screwdrivers: the driver often slipped … (Tools) trademark a screw having a square hole in the head into which a screwdriver with a square point ( Robertson screwdriver (trademark)) fits

Wanna Get Away? 9 Synonyms For Screwing Up We’ve all had moments where we’ve really and truly screwed something up. An epic mistake (OK, maybe not on a historic, global scale like the February 26, 2017 Oscars). But still, we’re human, and mistakes do happen. Amounts shown in italicized text are for items listed in currency other than U.S. dollars and are approximate conversions to U.S. dollars based upon Bloomberg's conversion rates. This Craftsman Robertson screwdriver is perfect for all of your square screw needs. The alloy-