Pleatco Filter with Free-Flow Core Technology for the purest water quality and durability Replaces OEM Filter Brands and Part Numbers: Baja Spas: Rainbow Dynamic 100 Coast Spas (Canada): Rainbow Dynamic 100 Pentair/Rainbow Plastics: Rainbow Dynamic 100, RTL100, RTL-100 Sonoma Spas: 100 Measurements: Length: 26-1/2" Outside Diameter: 5" Top Opening: 2-1/8" Bottom Opening: 2-1/8" # Total Sq. Ft. 100 Other popular brand part numbers Unicel Filter - C-4999, C4999 Filbur - FC-2397, FC2397 Aquakleen - AK3053, AK-3053 Manufactured by Pleatco, guaranteed highest quality or your money back Pleatco Part number: PRB100, PRB-100 UPC Code: 090164010038