Daggerz™ brand sheet metal screws are a high quality screw for aluminum and metal roofing applications. The sharp piercing point penetrates through metal easily and eliminates the need for any pre-drilling. This screw features a hex washer head and an aluminum bonded washer that creates a leak proof seal. The proprietary Dagger-Guard coating passes the 1000 hour salt spray test and provides excellent corrosion resistance that's suitable for exterior applications.