As of 2018, the pressure gauge is no longer included. PureSpa hot tubs manufactured after May 2017 are instead equipped with a pressure relief valve that automatically regulates the internal pressure. How does the pressure relief valve work? Once the tub is sufficiently inflated and firm to the touch, inflation can be stopped. There is no light or other indicator to indicate full inflation, but there is no need to worry about over-inflation - if the maximum pressure is reached, the valve will automatically start to release the excess air.