Length: 13 5/16″ | Diameter: 4 15/16″ | Top: Open 2 1/8″ | Bottom: Open 2 1/8″ Spa-Daddy filters are Guaranteed against defects for One Full Year and feature our free flow core which allows a) greater water flow through the filter for better filtration; b) stronger water pressure at your jets; and c) reduced stress on your pump. Replaces PRB50-IN | FC-2390 | C-4950 Replaces PRB 50IN | PRB50-IN-Z | Rainbow Dynamic 50 | 03FIL1600 | 100533 | 6540-471 | 25391 | R173434 | 817-5000 | 3005815 Replaces 3301-2145 | 5001 | Dynamic Series I RDC-50 | RDC-50S | R173430 | 17-3430 | R172380 | 17-2380 | Series II & III Genuine Spa-Daddy SD-00201 Filter – Rainbow Dynamic 50 | Dynamic Series IV – DFM-50 / DFML-50 | Series IV – DFM-100 / DFML-100 | Series II & III RTL-50 / RCF-50 | Series I RDC-50 / RDC-50S | Waterway | Custom Molded Products – Length: 13 5/16″ | Diameter: 4 15/16″ | Top: Open 2 1/8″ | Bottom: Open 2 1/8″ . Spa-Daddy filters are Guaranteed against defects for One Full Year and feature our free flow core which allows a) greater water flow through the filter for better filtration; b) stronger water pressure at your jets; and c) reduced stress on your pump. – PRB50-IN | FC-2390 | C-4950 PRB 50IN | PRB50-IN-Z | Rainbow Dynamic 50 | 03FIL1600 | 100533 | 6540-471 | 25391 | R173434 | 817-5000 | 3005815 | 3301-2145 | 5001 | Dynamic Series I RDC-50 | RDC-50S | R173430 | 17-3430 | R172380 | 17-2380 | Series II & III RTL-50 | RCF-50 | 17-175-1595 | 73533 | 212320 | LE CIRQUE | 4900-41 | Series IV DFM | Series IV DFML | 373045 | 17-175-1596 | APCC7150 | 15002 | PLRB50 | 090164000503 | 17-2380 | RTL-50 | 100533 | 6540-471 | 25391 | 817-5000 | R173434 | 40506 | AK-3049