In US the bike lights die required ty Law if you reading in low light conditions, The light can be attached to either the bike or to the cyclist but must be visible at least 500 feet to the front of the bicyde, so be careful how you position the light.Additional light! ng must be con¬sistent with the law specifying required lights and reflectors, so a rear light must be red.
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A front light. You must have a white light on the front of your bike that is strong enough to be seen from 300 feet. This light not only acts as a headlight to let you see where you are goi ng but it also makes it easier for approaching drivers to see that there is a cydist nearby.
A red rear light or reflector. On the bade of your bike, you must have a red reflector or light that can be seen from 500 feet away. Sinoe cy¬clists should ride with the flow of traffic it is mote likely that a car will be behind you. Thus, it is important that other cars can see you from the back. You may ever want to purchase a red light that blinks for even more visibility.