Pressure switch - Manufactured by Balboa - 1/8 inch MPT screw thread to attach to heater tube. Switching mechanism at top has 2 x flat spade connectors to attach the contact wire. Height: 75mm Width: 50mm.The only style of adjustable pressure switch Balboa have used in the last 10 years or more,.Used with systems such as M3TUV, Lite Leader and 2000 Value series including 2005LE with pressure switch - After a few years the wheel can become stiff to turn and you may find that you have to keep re-setting the switch, this is usually a good indication that the unit needs replacing.