Versatility in Application: This Heater Pressure Switch is compatible with various spa heater models from 2006 to the current ones, such as for Watkins, Solana, Caldera, and Hotspot. This wide range of compatibility makes it a versatile replacement part for many different spa systems, providing convenience for users in maintaining and repairing the spa heaters. Specification: 2-Wire 3-Pin Connector, 1/8" mpt, 1 Amp. Safety Function: .