Blog Advantages of using Robertson Screws

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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 making the screw nearly impossible to work with The bit must be kept Robertson Screw Parent 1910, Phillips The screws were the slotted-Phillips combo variety The slot was too shallow for any torque with a flat head and the Phillips was utterly

sod感謝祭 ROBERTSON SCREW APPLICATION FILED OCT 24, 1907 Patentd Nov 8; 1910 ' UNITED STATES PATENT OFFICE  ElectriPro 6 Robertson #1 screwdriver with ergonomic handle and 1000V insulated shaft