The OKY3604-3 is a charging module manufactured by OKYSTAR, designed to be used with 18650 sized power banks and USB devices. The module contains circuitry that enables charging, as well as voltage and current protection features. It is compatible with all standard power banks, USB devices, and other devices requiring a simple charging solution. The module supports all popular charging protocols, including but not limited to QUICK Charge 2.0 and 3.0, Power Delivery, USB-C Quick-Charge, Qualcomm Fast Charge, Apple Fast Charge, and Samsung Adaptive-Fast Charge. It incorporates advanced safety features to protect against short-circuiting, overheating and over-charging, making it a reliable and energy-efficient solution for those looking to rapidly charge their portable devices while on the go.