Elegantly designed switch for the DPSI dual power supplies (DPSI RV Mini, DPSI RV, DPSI 2001 RV, DPSI TWIN, DPSI TWIN Maxi, DPSI VREG). It generates the on/off signal for the electronic switch in the respective system and does not switch any power. The clever feature: the on/off operation is performed with an external magnet. When the magnet is inserted, the system is off; when it is pulled out (Remove before flight), the system is on. The magnet actuator is held in place by magnetic force automatically in the tank closure. The activated system is indicated by a brightly lit red ring. Error states or battery undervoltage are signaled, as before, by blinking codes. The switch concept is absolutely fail-safe, combining a reed switch and Hall sensor. The perfect switch - without unsightly holes in the fuselage! Mounting diameter: 15.5 mm, installation depth approximately 35 mm. Note: When used with the older DPSI TWIN or DPSI RV models (before June 2009), the DPSI must be sent in for minor modifications (free of charge). Delivery includes approximately 30 cm long connection cable, switching magnet, keychain, stainless steel screws, and counter flange.