The Unicel C-2305 hot tub filter is one of the smallest with an outside diameter of 2-3/4 inches and a hole on the top and bottom thats 1-1/16 inch. It fits select models of the Spa-In-A-Box.
Filter details:
- Unicel P/N: C-2305
- Diameter: 2-3/4″
- Length: 5-1/8″
- Top: 1-1/16″ Open
- Bottom: 1-1/16″ Open
- Media: 3.5 sq.ft.
- Filter Media: 3oz Reemay
- Pleat count: 76
Compatible replacement for:
- Pleatco PSB3.5
- Filbur FC-3120
How long will this hot tub filter last?
Due to the small size of this filter cartridge, it may require changing more frequently. Depending on spa use frequency and cleaning routine.
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