Unicel 5CH-45 Replacement Filter Cartridge for 45 Square Foot Freeflow Spas Legend<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Diameter: 5 5/16-inch; length: 10-inch</li><li>Top end cap: open， 2-1/8-inch inner diameter; bottom end cap: 1-1/2-inch male thread/mpt， 0-inch inner diameter</li><li>Pleat count: 225; filter media: 3-ounce reemay 2033; filter area: 45 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/41XdZF6jtHL.jpg" noproxy>