Features: 100% brand new and high quality. This is a 10W charge and discharge boost module. Designed with CR LED which is charge status indicator. Led indicator, OK LED is fully charged OR battery failure status indicator. Widely used for battery powered equipment,lithium batteries 18650 14500, UPS power supply DIY, solar charging, MP3/MP4 players, audio/video equipment, portable devices,Bluetooth applications. Specification: Charge voltage: DC5V(4.6V-6.5V) Charging current: 0-1A Full charge voltage: 4.2V+-2% Discharge current: 0-3.5A Discharge quiescent current: 200uA Discharge conversion efficiency: 78%-91% Output current: 0-2.1A(5V) Operating ambient temperature : -40 to +85 Storage temperature: -65 to +125 Size: 28*18*6.3mm / 1.1*0.7*0.2in Weight: 3g / 0.1oz (approx.) Package list: 1 * Module Note : 1, This module without lithium battery over-discharge protection. 2, In order to achieve more than 5W, it is recommended to use two or more batteries in parallel.