The OLIGHT OMNI-DOK II is an intelligent, universal dual-bay battery charger compatible with a wide range of rechargeable Li-ion (3.6V/3.7V) and Ni-MH/Ni-Cd (1.2V) cylindrical batteries (e.g., 18650, RCR123A, AA, AAA). It automatically detects the battery type and applies the correct, safe charging protocol, featuring multiple safety protections and LED status indicators.