Square headed screws are a relatively uncommon type of screw. That's not to say they don't have their uses, but they are generally a specialist type of fixing. Square headed screws feature a recessed square in the center of the screw head. They require a special screwdriver bit to tighten or loosen. Square headed screws come in a variety of sizes, when using them make sure the screwdriver used is exactly the right size. If you don't they'll round out very quickly.


See also:
Slot Head Screw
Phillips Head Screw
Pozidrive Screw
Dual Head Screw
Hexagonal Head Screw
Square Head Screw
Security Screw



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