Please note that： Before ordering, please make sure that the connector of the old charger is the same as ours. 1. If you receive a damaged item by the shipping, Please don't use the damaged item to charge. 2. Please use the products within one year. 3. Do not use over 12 hour per charge time. 4. Please charge in a ventilated environment. 5. Please don't cover the charger. 6. Please make sure your hands and the plugs are dry. Parameter 1. Input parameters: 100-240V 47-63Hz 2. Output parameters: 29.4V 4A 7S 3. Type of working battery: 24V Lithium Battery 4. Stable MTBF: >30000H 5. Efficiency: >87% 6. Material: PC UL94V0 Specification 1. Material: ABS + PC 2. Charger Model: CC(constant current) CV(constant voltage) 3. Operating Temperature: -50°F~122°F 4. Storage Temperature: -104°F~+176°F 5. Operating Humidity: 20~90%RH