Pentek Water Filter Housing - 10" Slimline replacement filter housing. 1/4" Female FNPT threaded ports. No pressure relief valve. Great as a stand alone water filter or as a replacement for broken sumps on RO systems. Cheaper than some sumps alone and assures that you can complete the repair of a broken sump on a RO system. There are many different thread patterns on the sump / cap assemblies. A mismatch may cause a leak. This housing uses a very common thread pattern. If the sump does not work as a replacement then also replace the housing cap. This will assure a perfect fit.