【USB-C charging cable enables easy charging】 You can charge 2 batteries simultaneously or individually, just plug it into a laptop, power bank, wall charger or car charger. Fast charging time is 1.5 hours, and the 9v rechargeable batteries have indicator lights that blink when charging and go solid when done
【3700 mWh provides longer battery life】 It lasts 3X longer than other 9v battery for smoke detector, and don't worry about running out of power while it working
【Recharged at least 1200+ times】 Multiple charges barely lose capacity, in the long run they will save you money on battery purchases and also reduce your environmental impact throwing away disposables, comes with a small carrying case too
【Advanced explosion-proof & leak-proof technology】 After a number of safety tests, the smoke detector battery is as safe as the built-in charger for cell phones and computers, and you don't have to worry about harming your expensive electronic devices
【Versatile rechargeable 9v batteries】 They holds a steady 9 volt, works for smoke detectors/fire alarms, guitars, wireless microphones, metal detectors, toy cars, thermometers, garage door openers, medical devices, etc. PS:The battery is not fully charged when it leaves the factory. Please fully charge it before use.