SD Pro-TekTM self-drilling fastener is developed for metal-to-metal building applications. The innovative SD Pro-TekTM with a larger head diameter limits wind uplift, and the concealed EPDM tubular washer system allows for a weather-tite seal. The engineered flat surface area on the SD Pro-TekTM also provides positive nutsetter engagement, preventing wobble during fastener install. Deep root cut threads give the SD Pro-TekTM Maximum Holding Power when installed into metal building panels!