Description
Replacement manifold internals for Pentair MasterTemp 400 and Sta-Rite Max-E-Therm 400 heaters (77707-0209). It regulates internal water bypass and distribution through the header to keep temperatures stable and the heater running efficiently. OEM internals sized for 400K BTU manifolds only; will not fit 175K-300K models.
Includes: Internal manifold assembly with bypass valve, springs, and hardware
