Single Pole Double Throw relays offer a normally open and a normally closed contact set in one relay. The moveable contact transfers continuity from one stationary contact to the other when the coil is energized or de-energized. Voltage isolation is then between opposing stationary contact and the moveable contact. As with our other High Voltage Relays GIGAVAC offers several design styles of vacuum and gas filled High Voltage Relays. Vacuum or gas as a dielectric each offer unique advantages depending on the application.