MI-450 Roof Drain Vent Stack Flashing Fitting Home » Products » CounterLine Plumbing Products » Roof Drains » MI-450 Roof Drain Vent Stack Flashing Fitting MIFAB® MI-450 Series mild steel stack sleeve with counter flashing and caulking recesses. Specification Sheet Catalog Catalog List Pricing Current Catalog: CLPB-2022 Return to Products