Tek screws, also called self-drilling screws, are self-tapping fasteners that have a drill bit end allowing them to be used for screwing materials such as wood and metal together without pre-drilling. Modified Truss Head Screws feature an oversized domed head with a flange, similar to an integral washer. Modified Truss Head Screws have a 100 degree undercut which creates a larger area beneath the screw's head for a larger bearing surface.