Cyclists seeking superior safety after sunset should snap up these Bicycle Wheel Valve Flash Lights from Shanghai Donya. Available in four different colors, the battery-powered bulbs impart instant recognition to night riders while offering day-trippers an added dash of bling.
Priced at around $3 each (and odds are you'll want a pair), the bulbs unscrew into two parts: an upper metal ring upon which the bulb is mounted, and a lower metal cylinder that holds three cr2032 lithium button batteries. Just load the batteries into the spring-loaded compartment and thread the base onto a standard bicycle wheel's tire valve.
Bicycle Wheel Valve Flash Lights come in four different colors: blue, pink, green, or rainbow that allow cyclists to complement their bicycle's frame color to some degree. If the bike isn't blue, pink or green, then the rainbow bulb is your best bet as it appears white when not in use.
Designed for operation after dark, these valve lights would appear to be activated when the two-part body of the device is twisted together to a certain tightness... we say “appear” because there's no visible ON/OFF switch at the Shanghai Donya product page.
We'll give them the benefit of the doubt for the moment, however, because nobody wants to constantly replace cr2032 lithium button batteries and unlike car and truck drivers, cyclists have no need to have any sort of lights on in daylight hours.
Caveats aside, we can see where Bicycle Wheel Valve Flash Lights would add an extra layer of safety to night-time and/or low-visibility cycling conditions. They run silently, are non-distracting to the cyclist, and provide onlookers with a colorful kinetic warning.