Pleatco Filter with Free-Flow Core Technology for the purest water quality and durability Replaces OEM Filter Brands and Part Numbers: STA-RITE INDUSTRIES Models: Posi-Flo PTM135, PTM-135, 135TX, 135GPM-TX, 135TXR Sta-Rite Replacement Part Numbers: WC108-70S2X, WC10870S2X Measurements: Length: 31-5/16" Outside Diameter: 8-5/8" Top Opening: 4-1/8" Bottom Opening: 4-1/8" # Total Sq. Ft. 137 Other popular brand part numbers Unicel Filter - UHD-SR137, UHDSR137 Filbur - FC-2570, FC2570 Aquakleen - AK-8022, AK8022 Manufactured by Pleatco, guaranteed highest quality or your money back Pleatco Part number: PSR137-4, PSR-137-4 UPC Code: 090164137001