Suitable for both indoor and outdoor use, these Photoluminescent Road Markers require no additional power to stay illuminated. They capture the natural and artificial light during the day and release them for a span of 8-10 hours post sundown. A great way to keep your lawns and patio lit up without spending extra dollars on electricity bills. Every set consists of 6 lights which measure 8.7 cm in diameter. They are both water and weather resistant so having them outdoors won’t be much of a problem. Bring on a new methodology in brightening up your lawns with road markers that look cool and don’t cost you extra bills too.