This guide is for general information only and is not legal advice. Laws change — verify current rules with your state DOT or a licensed attorney before relying on this for any legal matter. Read full disclaimer.
The rule
West Virginia requires lamp on the front emitting a white light visible from a distance of at least 500 feet to the front. For the rear, red reflector on the rear of a type approved by the division of motor vehicles, visible from 100 to 600 feet to the rear when directly in front of lawful upper-beam headlamps. a red rear lamp visible from 500 feet to the rear may be used in addition to the reflector. The rule applies whenever it is dark. See WV Code § 17C-11-5 (Lamps and other equipment on bicycles).
The cheapest way to stay legal in West Virginia is a USB-rechargeable front white light and a rear red light or reflector that meets the spec above. A $30 light set covers it.