High-quality 21700 batteries with a high real capacity of 5000mah and a constant current output of up to 10A. They are manufactured by the Chinese company BAK Power Battery, which is one of the leaders in the production of batteries and power cells for electric vehicles and electric transport. The quality of 21700 BAK batteries is not inferior to other well-known brands such as LG, Samsung, Vapcell, Keeppower, etc.