This corrosion resistant check valve is designed to use with Pentair pool and spa in-line automatic feeder models 300, 302, 320 and 322. Also fits Pentair pool and spa high capacity automatic feeder models HC-3315, HC-3330, HC-3340. Comes with 1-1/2-inch by 2-inch. Measures 5-inch length by 3-inch height by 5-inch width.