The NSA 25-I 251 Bacteriostatic Water Filter is a new water filtration unit designed for use with NSA Water Treatment Units. This filter utilizes bacteriostatic filtration technology, ensuring clean and safe water for consumption. The compact unit includes one filter and is compatible with the specified model, providing an effective solution for treating water in households or small kitchen settings. With the trusted brand of NSA, this water filter offers reliable and efficient water purification. Brand new sealed! Any questions, please ask! Thank You!tr4.3