Groco Vented Loop 1-1/2 in. w/Mounting Hardware Moeller and can be used above

and can be used above or below the waterline

It feathers to a fine edge and is also more economical for large fairing jobs

ISO 12401 Deck Harness

Warranty: Limited Lifetime (Original Owner)

Groco Vented Loop 1-1/2 in. w/Mounting Hardware Moeller and can be used aboveHVL SERIES VENTED LOOP Allows air to enter to break siphon, but does not permit air and odors to escape. Cap is threaded 1 2 NPT to accept a barb fitting if you wish to vent overboard. Overboard venting is required if HVL series is used in an exhaust system. HVL series vented loops assure clog free anti siphon protection for sanitation or engine exhaust systems. The oversized vent valve can easily be removed for inspection or cleaning without tools.