The Nitecore UM2 Intelligent USB Dual-Slot Charger is an efficient charger for high-drain battery cells of various capacities and sizes (18650 / 20700 / 21700 / 26650), alongside automatic type detection, various inputs, and new restoration mode. The special restoration mode can potentially revive overdrawn or drained Li-ion batteries, extending the life of them. With up to 1500mAh charging speed per slot, the Nitecore UM2 has two bays to automatically detect Li-ion, IMR, Ni-MH, and other various battery types and apply the proper charging settings optimal to maintaining battery health. Furthermore, the Nitecore UM2 has a slew of internal protections to guard against failing or damaging the batteries while also maintaining optimal heat dissipation from the durable and flame retardant PC chassis.