Unicel C-8325 Replacement Filter Cartridge for 125 Square Foot Sundance Spas， Universal Length<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Diameter: 8 7/16-inch; length: 18-inch</li><li>Top end cap: closed with 3-step edge， 0-inch inner diameter; bottom end cap: open with beveled edge， 2-1/2-inch inner diameter</li><li>Pleat count: 201; filter media: 3-ounce reemay 2033; filter area: 125 square feet</li><li>Get more efficient filtration and better water clarity with Unicel filters</li><li>Longer time between cleanings; meets oem specifications</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41fS0so7fNL.jpg" noproxy>