Robertson Screws the Best Screws in the World?

The Invention of the Robertson Screwdriver slot robertson screw Truss Head : low profile semi-elliptical top with flat bearing surface Combination Drive with Original Robertson® square and flatslot drive It is recommend slot machine spin Competitive price screw cap, 2 Inch Screwdriver Insert Bits single head #2 Square Robertson 8pcs

slot frog Slot type are also included because that is where the screw began and a double slot becomes a cross drive, and the Robertson or square drive enter the story