Compact, aero-post compatible rear bike light featuring a Daytime Flash mode and our custom programmed Alert technology Equipped with Lezyne`s Wide Angle Optics lens that provides up to 270Ì_å of visibility and two high powered LEDs When decelerating, the light will turn solid like a brake light and then provide a distinct flash pattern once stopped to alert riders or vehicles from behin, then change back to its previous output mode once the rider resumes his or her ride Co-molded construction is super light, yet durable and has an IPX7 waterproof rating The KTV Pro Alert Drive provides up to 75 lumens (Daytime Flash) and five output/flash modes Features an integrated USB stick for convenient cable-free recharging and offers up to 14 hours of runtime