The niterider solas 100 rear light is a bright and eye catching light with different flash settings and a great battery life the solas 100 has two powerful leds 4 modes 2 flash2 steady and is usb rechargeable the two bright red leds produce a super attractive 100 lumens which when working with the correct mode in comparison to what weather youre riding in who you are riding with or how much battery is left in the light is super effective niterider have implemented what they call gro