Powered by two 2016 Lithium coin cell batteries, the INOVA Microlight is an ingenious micro LED flashlight, with a surprisingly powerful performance - it has an effective range of up to a 50-feet, and one-mile signal visibility. The Microlight also features four lighting functions and a water-and-crush-resistant body, plus a stainless-steel universal clip that attaches easily to keys, zippers, purses, backpacks, and any number of convenient locations. Water and crush-resistant polycarbonate body Four modes: high, low, strobe, and signal Easy open/close for battery replacement Effective range of up to a 50-feet One-mile signal visibility