Detect UV-reflective materials that are invisible to the naked eye with these bulbs. They contain a blue filter that absorbs the visible light they produce while allowing long wave ultraviolet (UV-A) light to pass through. They appear black when turned off. These bulbs are not for use in bug zappers. A bulb’s estimated yearly cost is based on 3 hours of usage per day at $0.11 per kWh.

Bulbs cannot be sold to the listed areas because they exceed local regulatory limits on mercury.