Purestart Spa Pre-ilter 1-Micron is the perfect filter for filling your spa with high quality water. Removes ultra-fine particles from spa water to save you on time, effort, and chemical cost, so you can get right into enjoying our spa ! It's easy to use - just attach to the end of your garden hose, turn on the faucet, and begin filling your spa with high quality water. After use, simply rinse it off and re-use it again and again! With this filter you typically can expect to be able to refill the average spa 20 or more times. Capacity : for spas and small pools up to 10,000 gals. Length : 10" (25.4 cm.) CAUTION: This filter does not remove dissolved metals. For high metal levels, use the METALTRAP™ Filter.