History of the Robertson Screwdriver

Robertson Square Drill Bit Set (10 Pack slot robertson screw Slot heads are rubbish to anyone who installs large numbers of fasteners and drivers on Phillips fasteners cam out very easily, usually making a slot88 slot This screw is actually a Canadian invention! Back in the late 1800s and early 1900s, the only screw available was the slot head screw However,

slot gachor By Susanna McLeod Special to Ontario Construction News Have you been startled by your screwdriver slipping out of the slot and damaging