9 Guardian Pool Spa Filter Replaces Unicel C-4335 - Pleatco Prb35-In - Fc-2385 -Rainbow Dynamic Series Iv -Bottom Opening: 2 - 1/8" -Top Opening: 2 - 1/8" -Outside Diameter: 4 - 15/16" (Also replaces 5") -Length: 9 - 1/4" (9 1/4") Filter Area: 35 SQ FT