XCSOURCE 4000LM CREE XML L2 LED 5-Mode Zoomable Headlamp + 2 x 2600mAh 18650 Rechargeable Battery + Car Charger + USB Cable LD419 Headlamp has adjustable focus. Powered by 2 x lithium batteries (2600mAh). Adjustable and flexible headband. The length of the headband is adjustable for your use. Made of elastic fabric Circuit operating voltage is large and makes better use of the batteries.