Optimize performance- Optimize the feture of the pump and extend the service life of the equipment while filtering out dirt and debris. Fuctions- Removes dirt effectively for pools and hot tub, keeps your spa debris free, so as to keep water clean and fewer water changes times. Economical filters-Package include 2pcs replaceemnt pool filter.Change filter regularly usually every 4-6 weeks to enjoy healthy water quality. Dimensions- Outer diameter 104mm, inner diameter screw diameter 60, height 82mm.