About the Ion 100 R Front Light - 100 Lumen The Bontrager Ion 100 R Front Light is ideal for cities and towns, to make you safe and seen. The 100 lumen output, is produced through the a wide angled, focused optics lens, which is visible from upto 500m away in day time. If you are commuting during the daytime, 100 lumens are all you need to be seen by cars and other road users. The light also features an auto-brightness light sensor, so it will save you power where needed. Key Features Brightness: 100 Lumens Power Source: 250 Li-Ion rechargeable battery Run Time - 100 Lumens: 1.5hrs - 50 Lumens: 3hrs - 5 Lumens: 16hrs - Night flash: 7hrs - Day flash: 5hrs Mounting: handlebar or on-bike mounting Light modes: 5 modes Weight 27g Extra Features - Day time visibility - Integrated light sensor auto-adjusts brightness in flash mode Lighting Buying Guide