Features: Controller ER-150 V-1B 2S powered storage system seamlessly integrates with the simple door closing system. High accuracy of the system, easy to operate. After connecting three sets of retractions on the controller, the system will automatically start the door system. The system will not be able to start the gate system if one of the three fallbacks on the controller is not connected. The system automatically recognizes situations where interface modes are abandoned, but other retractions do not work. Specifications: Condition: 100% Brand New Optional Type: Retractable System Controller, Retractable Landing Gear + Controller Controller: Working voltage: 5V - 6V Controller size: 53 x 32 x 10mm / 2.1 x 1.3 x 0.4in Controller version: v-1b (2S power supply) Suitable for 120mm-150mm EDF jet or other plane up to 12-15kgs Retractable Landing Gear: Working voltage: 7.4 v-8.4 V (2S li-po) Angle: 90 ° Speed: 5.2 seconds (5v) - 4.3 seconds (6v) Strut hole diameter: 12mm / 0.5in Torque: 15kg cm Retracted size: 27 x 80 x 22mm / 1.1 x 3.1 x 0.9in Retractable mounting plate size: 36 x 48mm / 1.4 x 1.9in Package List: 1 x ER150 Controller 1 x Plug Cable Or 3 x ER150 Retractable Landing Gear 1 x ER150 Controller 1 x Plug Cable 1 x Wrench 1 x Connection Rod 5 x Screw 1 x Nut (Based on your choice)