Manufactured with anchor flange, stainless steel waterproofing membrane clamp ring with screwed gravel stop, adjustable stainless steel extension flange, underdeck clamp and standard self-locking stainless steel dome strainer. Used in any type of flat roofs and gutters. Dome provides for efficient drainage of rainwater and prevents debris from entering the drain line. Adjustable extension system can be configured to the thickness of insulation on top of the roof deck without the need for gaskets. Anchor flange and membrane clamp in groove design provides for secure grip of membrane and roof flashing materials.