Replacement O-ring for Sta-Rite pump unions, designed to seal connections in pool and spa systems. Fits Sta-Rite IntelliPro, Max-E-Pro, Dyna-Pro, and System:3 filters with 2" unions. Made of durable Buna-N rubber, ensures leak-free performance in chlorine-resistant environments for reliable operation.Compatible with Sta-Rite IntelliPro VS, Max-E-Pro, Dyna-Pro, Dyna-Glas, and System:3 filters (S7M120-S8M500, S7D75-S8D110), per Aladdin specs.Measures 2-5/8" ID by 2-7/8" OD with 1/8" thickness, constructed from black Buna-N rubber, matches Sta-Rite U9-362 OEM part.Installs into 2" union fittings on pumps or filters, requires no tools beyond disassembly, seals under pressure up to 50 PSI, per Aladdin documentation.Delivers a tight, lasting seal with a quick swap, keeping your service jobs efficient and client systems leak-free with minimal effort.