1. Compatibility: This ECX271261 pressure gauge is suitable for Hayward pool filter star clear plus cartridge, pro and hcf series sand filter models s244sv, hcv20715, c12002, s270t2. Also fit for hayward perflex series extended cycle d.e. filter and multiport valve models ipfppts, sp071620t, sp0710x62. 2. Easy to Install: Installation for this hayward pressure gauge is easy. No special tools or expertise required. Simply replace your old dial gauge with this one and get back to enjoying a clean, well maintained pool. 3. Accurate Reliable: With a clear, easy to read dial, this pool pump pressure gauge provides precise pressure readings, helping you monitor your pool filter's performance and know exactly when it is time to clean. 4. Construction: Built to withstand the demands of pool and spa environments, this gauge is made from high quality materials that resist wear, ensuring long lasting use.