CatEye: Pumping out an attention-grabbing 300 lumens with OptiCubeTM lens technology, the versatile ViZ300 stands out with the power of Daytime HyperflashTM mode and the friendliness of Group Ride mode. 3 LEDs (300 lm) Highly visible during daytime 300 degree visibility Long rear beam projection OptiCubeTM lens technology Lithium-ion rechargeable battery USB-C rechargeable (USB-C cable not included) Low battery indicator Four light modes (Constant / Flashing / Group Ride / Daytime HyperFlash) Mode memory function Battery Auto Save (The mode automatically changes to flashing when the battery power gets low.) New seat post bracket SP-15 which fits contemporary (kammtail) aero seatpost Snap SystemTM Dimension: 25 x 75.5 x 34 mm Weight: 47g (with batteries) Light source: Red LED X3 Battery :Li-ion rechargeable battery Runtime: Constant (30 lumens):5hrs Flashing: (30 lumens):45hrs Group Ride (15 lumens):10hrs Daytime HyperFlash (300 lumens):10hrs Recharge time: 3hrs (0.5A) Mount size: 21.5-32mm. Fits up to 130mm outer circumference. (SP-15) Water resistant: IPX4 Other: Battery auto save, Low battery indicator, Light mode memory