6", 6RV-SC, Storm Collar, Round, Type B Gas Vent Storm collar provides a seal to prevent water from leaking between flashing and pipe Used above the roofline and requires hi-temp silicone sealant on the inner edge RV series offers round gas vent pipe and fittings for residential, commercial and industrial applications Features a snap together, non-positional lock system, die formed ends and eliminates the need for all cutting, fitting and special engineering