Slim OnePlus 9/9R/9 Pro Power Bank Charger Case with Extended Battery Life

Power Bank Case For Oneplus 9 Pro Battery Charger Case portable Extended charging cases For Oneplus 9 9R USB Powerbank Cover Battery capacity: 6800mAh Rated capacity: 4000-5000mAh Instructions: 1. Click once to start charging. 2. Tap twice to turn off charging -Battery type: lithium-ion polymer battery -Material: High Quality Silicone+plastic Instructions: Click the switch to start charging. Press and hold the switch to turn off charging. NOTE: Portable Battery charger case has two regular standard of capacity , one is the battery capacity, one is the rated capacity. Why exist this difference? The most important reason is the conversion rate. Because most of power bank's battery voltage is 3.7V, and power bank needs to increase the voltage to 5V when charging the mobile phone, which making the power bank's conversion efficiency only 3.75/5=74%, Also include generated heat when battery voltage boosting, and various of wire consumption, Electricity and self-consumption. these points add up to account for 30%-40% of the power of the mobile power source. So the 5,000mAh power bank can really be used by us only about 3000-4000mAh. Also, The conversion rate of the entire mobile power industry is basically in the range of 60%-70%. Please kindly noted. Please search on Google if want to know the details!