The standard slotted head is very best utilized using a flat screwdriver, even though the cross-formed indention is ideal suited to some Phillips screwdriver. A Robertson screw provides a sq.-formed indention and needs a matching driver head. The length of these screws differs, but most drywall screws have flat heads https://screws65308.ziblogs.com/28621801/the-definitive-guide-to-wood-screws