This Moeller Anti-Siphon Valve is a must-have for any plumbing or ventilation system. Made of durable aluminum and featuring a 3/8" Barb NPT design, this valve is perfect for use on boats and other vessels. The valve is designed to prevent siphoning and ensure that your system operates smoothly and efficiently. With its high-quality construction and reliable performance, this Moeller Anti-Siphon Valve is ideal for use in a variety of plumbing and ventilation applications.