The Streamlight PolyTac X is a 600 lumen tactical light with compact and lightweight polymer construction that makes this light perfect for personal use. With integrated TEN-TAP programming, user can choose the order of three modes: high/strobe/low (factory default), high only, and low/medium/high. By double tapping the switch, a strobe setting can also be activated. This particular model comes with two (2) CR123A batteries, but has multi-battery versatility and can accept the Streamlight 18650 Li-Ion 3.7v USB battery with integrated USB charging port.