Features: 1. REUSABLE WASHABLE FILTER: Regular replacement of the cartridge can prove costly. These washable and re-usable foam filters will reduce your costs. 2. HEAVY-DUTY FOAM FILTER: Superfine and heavy-duty filter sponge can capture and absorb fine dirt and sand. 3. REPLACE ONLY EVERY 2 WEEKS: Each ink cartridge only needs to be replaced every 2 weeks allowing you more time to enjoy the pool. 4. SPARKLING CLEAN POOL: Replace the filter element of the pool let yourself rest and relax in the sparkling clean pool. 5. QUALITY MATERIAL: Made of high quality material durable and practical to use. The cartridge filter is to keep your water clean and fresh. Prevents dirt from entering the pump and heater and prolongs service life. Notice: Actual color may be slightly different from the image due to different monitor and light effect. Please allow 1-3cm deviation due to manual measurement. Description: Material: Sponge Color: blue Type I Size(HxD): 8.8x7.8cm/3.46x3.07in(Approx) Center Hole Drilled: 28mm(Approx) Type II Size(HxD): 13.4x10.4cm/5.27x4.09in(Approx) Center Hole Drilled: 52mm(Approx) Type VI Size(HxD): 8x10.4cm/3.14x4.09in(Approx) Center Hole Drilled: 52mm(Approx) Type D Size(HxD): 9.5x10.8cm/3.74x4.25in(Approx) Center Hole Drilled: 52mm(Approx) Type H Size(HxD): 10.2x9cm/4.01x3.54in(Approx) Center Hole Drilled: 30mm(Approx) Type S1 Size(HxD): 7.4x10.8cm/2.91x4.25in(Approx) Center Hole Drilled: 40mm(Approx) Type A Size(HxD): 20x10cm/2.91x3.93in(Approx) Center Hole Drilled: 40mm(Approx) Type B Size(HxD): 25.4x14.5cm/10x5.7in(Approx) Center Hole Drilled: 45mm(Approx) includes: choice 1: 1 x Filter Sponge choice 2: 2 x Filter Sponge "