The Catey Volt 500 XC & Rapid X2 light set are for commuters who want the best lights without breaking the bank. The Cateye Volt 500 XC is the brightest light in the XC series & is ideal when strong output is needed. With 500 lumens of output the Volt 500 XC is perfect for commuters who encounter longer stretches of darker roads & cycle paths & who want to be able to see where they are going as well as be seen. This power, coupled with the sleek profile of the light also makes it absolutely ideal for training after the sun has set. At the back the Cateye Rapid X2sits neatly begin your seatpost & puts out up to 80 lumens on six different modes. Both front & rear lights are USB (Universal Serial Bus) rechargeable & both come with rubber strap mounts that make the lights quick & easy to put on & take off your bike. Cateye Volt 500 XC Front Light Double click to high 4 modes: High / Low / Hyper constant / Flash Runtime: 400lm: 1 hr, 100lm: 8 hrs, 500lm: 20 hrs, 100lm: 30 hrs Recharge time: 7 hours USB (Universal Serial Bus) rechargeable Proprietary Opticube lens Cateye Rapid X2 Rear Light Ultra bright strip LED technology Li-Polymer battery technology up to 80 lumen output Complex circuitry for safe charge & discharge USB (Universal Serial Bus) recharge (2hrs) O-Ring attachment 6 modes: High / Low / Flashing / Rapid / Pulse / Vibration Runtime: 500lm: 1 hr, 100lm: 8 hrs, 500lm: 20 hrs, 100lm: 30 hrs Dimensions: W 22.5 x H 27.2 x L 73.2mm