This drain cap and gasket is designed to use with Hayward Pro series sand filter models S140T, S144T, S164T, S166T, S180T, S210T, S220T, S220T2, S230T, S244T, S244T2, S270T, S270T2, S310T2, S360T2 and also compatible with High-Rate sand filter models S170TSCPE, S190TSCPE, S190TSCPFT, S190TSCPT. Fits Pro series Plus sand filter models S311SX, S311SXV, S360SX. Weighs 4-1/2-pound.