Dock Edge + Inc"s solar light mounts easily on any 4x4 (3.5" x 3.5") wooden post. It is ideal for decks and patios or fencing where ground or floor level lighting may not be desirable. It features a corrosion-free construction, automatic on-at-dusk , powerful solar charging panel, brite white LEDs and rechargeable batteries. This model incorporates a clear polycarbonate lens secured between durable PVC upper and lower housings. It includes replaceable rechargeable batteries. Each post top casts ample light to illuminate immediate areas such as stairways, gates or ramps for safety and convenience.