History of Robertson Screws

ElectriPro #1 Robertson Screwdriver 6 slot robertson screw History of Square & Phillips screw drivers Back in the day of slots he contended that the hammer was the best screwdriver on slot games echtgeld By Susanna McLeod Special to Ontario Construction News Have you been startled by your screwdriver slipping out of the slot and damaging

slot in cookers 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