K92F Power Bank Case w/ Bluetooth-compatible Speaker Function Portable DIY 10x18650 Charge Storage Box Shell Dual USB OutputFeatures: LED display, you can see the rest power clearly.Small size and lightweight, convenient to carry.Can be used to charge for multiple devices, intelligent matching current, no damage to the machine.Widely application, suitable for outdoors like climbing, hiking, riding, etc., fit for teens, adults, seniors.Multifunctional, it has bluetooth-compatible speaker function, design with flashlight, can be used at night.Specifications: Material: PlasticSize: Approx. 187x79x44 mm/7.36x3.11x1.73 inColor: White/Black/GreenPackage Includes: 1x Power Bank CaseNote: "+" is the positive pole, connected to the positive pole of the battery, "-" is the negative pole, connected to the negative pole of the battery, the spring will burn when installed reversely, please be careful.Please insulate the damaged battery, do not put damaged batteries, otherwise it will cause the battery to short circuit and damage the product.Please use a flat head 18650 battery, do not incorporate a seriously aged battery, otherwise it will affect the use, such as intermittent charging.Do not support pointed batteries, please do not use batteries with flashlight or strong light words, it will under-voltage protection, unable to supply stable power.Using a poor battery may not be able to input, it will be disconnected after charging for a while, especially the batteries removed from notebook, electric drill, and electric car.Please notice that the product include NO batteries.