These are flat top truss head screws. They are black oxide coated with Phillips drive. These are commonly used for TMLAB replacements and for upgrades to holster and sheath mounts. These screws are heavy duty and are hard to find.
Head Type = Flat Top Truss Head
Length = .500 (1/2") (from under head)
Overall Length = .591
Head Diameter = .400 (+/- .004)
Black Oxide Coated
(1 QTY = 1 Screw)