Clarathon Premium Hot Tub Filters

Measure Diameter & Length

Note your old filter’s end cap Diameter (edge-to-edge) and Length (cap-to-cap) rounded to nearest ⅛". Exclude any handles/fittings. Measure any openings or fittings per info below.

Measure Opening Diameter

Drop-In filters often have 2 open ends, or just 1 with closed top. A few Screw-In filters have inner threads with handle top. Measure inside diameter of opening(s). Match to listing specifications.  

Measure Fitting Outside Diameter (OD)

If your filter has a fitting, note the style (Coarse Thread, Fine Thread or Male Slip) and determine OD. Match to listing specifications. Refer to photos.  

Use Menu to Narrow Filter Selection

Noting old filter's dimensions:

1. Choose Type: Drop-In or Screw-In.
2. Got Part #? Try: [Search these products]. No match? Go to 3.
3. Pick: Spa Brand, if known. No match? CLEAR Brand (x). Go to 4.
4. Select: Diameter & Length ranges. Dimensions may vary ± ⅛".