-Power by: Rechargeable lithium polymer battery, USB cable charging - 2 hour charge time 

-4  modes to choose: steady on > slow cycling flash > quick cycling flash > synchronized flash

Install or remove without any tools, easy to be fixed on seat post ,frame or tail of bike Secure, remains securely locked in position, even during off-road use. It is water and shock resistant. Super bright led light makes you visible on the road in dark. Suitable for the professional or casual bicycle rider.