Tap-Flex® Thread-Forming Structural Screws Print Tap-Flex® Thread-Forming Structural Screws are thread-forming, dual heat treated self-tapping fasteners that provide the strength, ductlity, and resistance to embrittlement failures required in critical curtain wall and dissimilar metal applications. Tap-Flex fasteners are designed to offer a replacement option for traditional nut and bolt assemblies. These fasteners provide an excellent solution for blind connections. The patented E-Form® segmented thread profile design improves installation and forms threads that provide increased thread engagement. Read Less