Forespar MF 840 Vented Loop - 1-1/2

Forespar Vented Loop installations ensure that fluids will not siphon from tank to tank.  Vented loops are commonly used in the marine toilet system and engine cooling system.  The simple duckbill one-way valve system incorporated in the top of the loop allows air to enter the line when not in use, yet effectively seals as water or other fluid passes through. Precision molded in high-strength non-corrosive Marelon®, neither vent nor loop will corrode.  The duckbill one-way  valve is designed to seal properly if particulate matter is present in fluids.  The optional Vent Barb allows venting to the outside of the hull via a 1/4" tube. 1 1/2" barb 5" in height 7 3/4" wide