【Warning】Don't connect positive and negative terminals reverse. If you find that the positive and negative terminals are mismatched, there is a photo tutorial available for reference. Please ensure port compatibility before purchasing 【High Capacity】7.4v 2500mAh Li-ion rechargeable battery, which can make your device get longer usage time. Port type: JST-XHP-2 , cable length 3.87 inch, size: 2.6 * 1.45 * 0.76 inch, weight only 93g, easy to carry 【Wide Compatibility】Compatible with speaker/ walkie talkie/ X6 transmitter/ bluetooth boom box/ portable DVD player/ remote control toys/ outdoor lights and so on 【Low Self-discharge Rate & Long Life Span】Lithium-ion battery has the lowest self-discharge rate among all types of batteries, generally less than 1%/month, less than 1/20 of NiMH battery. long life span, can be recharged up to 3000 times. High and low temperature adaptability, can be used in the environment of -20 ℃ - 40 ℃ 【Smart Chip】Professional battery management system with built-in smart chip provides reliable overcharge, overdischarge, short circuit, overheat, overvoltage, overcurrent multiple safety protection functions, ROHS, CE certified, in line with environmental standards Sparkole 7.4V 2500mAh Li-ion Rechargeable Battery for Speaker/ Remote Control Toy/ Bluetooth Boom Box/ Portable DVD Player/ Outdoor Lighting