K-20/21 Professional Series Powerful Bright 2000 Lumen Dual LED Headlight- Bar or Helmet Mount- Quick Release- Waterproof 4 Cell Li-ion Rechargeable Battery- 2000 Lumens of Pure Powerful Light to See the Road or Trail. Four Power Levels 10, 40 70 and 100% for Varying Intensity and Battery Life. 3+ hours on Full Power Waterproof Li-Ion 4 Cell 18650 Battery Pack. Waterproof Connections. Up to 20 hours Run Time on Lowest Setting Quick Release Bar Mount, O-Rings for Bar or Helmet Mount, Velcro Helmet Strap Included Solid Aircraft Aluminum Construction. Metal Switch for Positive Power Clicks. Nice Carrying Case with Zipper to Keep Your Light and Components Together