Use silicone sealant between base & surface. Secure with sheet metal screws. Multi size pipe sealing range, molds to metal, plastic, etc. 5-9" Masterflash Flexible roof flashing Ideal for corrugated roofs Slides over pipe, for pitch to 45 degrees Use silicone sealant between base & surface Secure with sheet metal screws Multi size pipe sealing range, molds to metal, plastic, etc. Non-fading epdm collar, rated 212 degree fahrenheit continuous heat Approved for type b installations.