With the Flash Headlight/ Taillight Combo youre equipped with everything you need to be seen—day or night. It features up to 70 lumens in the front & 20 lumens in the rear & it features the versatility of four light modes ranging from steady & strong to flashing & brilliant. Increase your visibility with the Flash Headlight/ Taillight Combo. Headlight: 20- to 70-lumen output. Headlight: 2 hours to 24 hours runtime. Tail light: 5- to 20-lumen output. Tail light: 2 hours to 20 hours runtime. Flexible mounting system works with handlebar & seatposts from 22.2mm up to 35mm in diameter as well as most seatstays helmets & saddle bags. Four headlight modes including: Steady (55 lumens) Power Flash (70 lumens) Disco Flash (55 lumens) Eco Flash (20 lumens) Four taillight modes including: Steady (10 lumens) Power Flash (20 lumens) Disco Flash (14 lumens) Eco Flash (5 lumens)