Features: Good product with high quality material. With stable performance, it is practical and durable. Fine workmanship and perfect style. Fashionable design, match with your Helicopter perfectly. It can help your Helicopter fly much higher and quicker, more secure. Easy to install and convenient to use. Suitable for: Wltoys V911 F929 F939 Helicopter Airplane Description: Item Name: X4 4 in 1 battery charger Charging 4 battery at one time Over charge protection Short circuit protection