High temperature shut off switch.
Bypass pressure relief valve.
Chemical selector valve has 3-way setting: off, prime, and chemical. Fits most Prochem, BLUEline, HydraMaster and Sapphire Scientific truck mount units.
This 1/8" female pipe thread chemical metering valve will fit most Prochem, BLUEline, Sapphire Scientific and HydraMaster units.
General Pump 180° thermal relief valve.