Tail lights for your helmet. Weighs less than one ounce including the battery. You won't notice the weight, but traffic will notice you. Four flashing LEDs signals up high in motorists' line of sight.
Attaches to the rear or lateral ventilation holes of your helmet. The on/off button is mounted to your chin strap for easy access via unobtrusive cables.
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Busch & Müller 4DToplight Permanent Bike Tail Light