*Money Saving 3-Pack* When you order this product, you will save $3.00 off of the normal retail filter price. You will receive 3 genuine Unicel replacement filter cartridges. This 3 ounce top load filter has a semi-circular handle top and a 1-1/2" male threaded fitting bottom with 178 pleats. It is rated for 40 square feet. The Unicel spa filter cartridge should be inspected monthly and replaced every six to eight months if the spa is maintained properly. Save $3.00 when you order the 3-Pack.