Phillips screwdrivers Have got a cross-formed suggestion that matches right into a corresponding recess in the screw head. Pozidriv screwdrivers are similar to Phillips but have extra points of Make contact with for greater grip. Robertson screwdrivers have sq.-formed guidelines that in shape snugly to the recess from the screws. https://typesofdecking19516.pointblog.net/5-tips-about-types-of-screw-heads-for-screwdrivers-you-can-use-today-70811390