Compact aero-post compatible rear bike light featuring a Daytime Flash mode & our custom programmed “ Alert” technology. It’s equipped with our Wide Angle Optics lens that provides up to 270° of visibility & two high powered LEDs. When decelerating the light will turn solid like a brake light & then provide a distinct flash pattern once stopped to alert riders or vehicles from behind. The light will then change back to its previous output mode once the rider resumes his or her ride. Its co-molded construction is super light yet durable & has an IPX7 waterproof rating. The KTV Pro Alert Drive provides up to 75 lumens (Daytime Flash) & five output/flash modes. & it features an integrated USB (Universal Serial Bus) stick for convenient cable-free recharging & offers up to 14 hours of runtime. • Custom programmed Alert technology.• Max. 75 lumens.• Max. 14 hours runtime.• Five Output modes.• Integrated USB (Universal Serial Bus) Stick.• Waterproof.