A Robertson screw, normally called a sq. or Scrulox screwdriver, has a square-shaped slot within the screw head plus a sq. projection within the tool. it can be specified as an ANSI form III sq. Middle screw. The socket https://sachinnpnc311054.ampedpages.com/5-tips-about-types-of-screw-heads-you-can-use-today-56136689