The Doulton W2313080 HIP/HCP Filter Housing Wrench is used to remove filter housings on HIP, HCPS, and DIY systems. Lightweight and portable, it makes replacing water filters easy. The Doulton HCPS/HIP/DIY wrench should not be used to tighten the housings. Over tightening the housing can cause damage to the o-rings and make re-opening the housing difficult. You should only hand tighten the housing. This housing wrench can be used with Doulton HCPS Countertop Filter Systems and Doulton HIP/DIY under Sink Water Filter Systems.