Pro Vent Anti Siphon Trap Vent automatic anti-siphon trap vent used as secondary venting. Simply hand tighten, no thread seal needed. Must be installed in accessible location with free flow air; do not install in sealed wall cavity. 1-1/2" MPT threads. If you are not satisfied for any reason products may be returned within 14 days of shipment for a credit or exchange (provided the product is undamaged), except where noted, NOT RETURNABLE. Return documentation should clearly specify credit or exchange. Returned items must be in the original packaging. All returns must include a return authorization (RGA) number that can be obtained by contacting our Customer Service Department. Original shipping cost deducted. Reference to brand names and numbers are for reference only, and not meant to imply that they are made by that manufacturer (OEM). Sometimes images shown are generic and not meant to infer that they are actual. The parts will work as intended and are high quality and precision tested. If you are not satisfied for any reason products may be returned within 30 days of shipment for a credit or exchange (provided the product is undamaged), except where noted, NOT RETURNABLE. Return documentation should clearly specify credit or exchange. Returned items must be in the original packaging. All returns must include a return authorization (RGA) number that can be obtained by contacting our Customer Service Department. Original shipping cost deducted. Reference to brand names and numbers are for reference only, and not meant to imply that they are made by that manufacturer (OEM). Sometimes images shown are generic and not meant to infer that they are actual. The parts will work as intended and are high quality and precision tested. Track Page Views With Auctiva's FREE Counter