The Power-Ion battery packs are special batteries for powering the receiver system and the servos in the model. The main advantages of the Power-Ion batteries are high mechanical resistance due to their metal cell cups and long life. No balancer is required for their operation and charging, and short-circuit protection is activated in the event of a short circuit with a current higher than 150A. Overcharge protection is activated when the charging voltage rises above 5V per cell. The batteries are functional even at very low or very high (-10 - +60 ° C) temperatures. Each Power-Ion battery pack is equipped with a two-wire cable with JR connector and a two-wire cable with MPX connector for connection. For higher currents we recommend to connect the receiving system via the MPX connector and to use the JR connector as charging connector. Both cables have the same length. The Power-Ion battery packs are delivered in a plastic mounting frame, in which the batteries are fixed with the enclosed Velcro tape. This mounting frame is screwed into the model via rubber grommets to protect it from vibration. Insert the enclosed brass grommets into the rubber elements so that the side with the contact surface faces the mounting surface. This prevents the rubber elements from squeezing together. - perfect for models with HV servos or via external BEC/JETI Central Box 400 technical data: Nominal capacity: 6200mAh Nominal voltage: 7.2V Charging voltage: 8.4V Cable length (1x MPX cable + 1x JR cable): 135mm each Weight: 230g (incl. mount) / 208gr. without mount Dimensions: 104x47x50mm (with mount) / 70x39x40mm (without mount) Continuous current max:40A Short-time current max: 80A Charging current max: 8A (via MPX connector).