Replacement water filters come in all shapes, sizes, and types. The replacement filter you need will depend on the type of water system you have and the contaminants you wish to filter out. Some systems require proprietary filters which cannot be subsituted and usually cost more. US Water Systems does sell proprietary filters, however, all of our water systems use industry standard filter sizes. In most cases, industry standard filters are interchangeable and can be more easily obtained. You can determine the size of your water filter by measuring the diameter and length in inches. Industry standard filter sizes are as follows:
2.5" x 10" 2.5" x 10"2.5" x 20" 4.5" x 20"