Greenlighting High End Solar LED Post Cap Light for 4 x 4 Wood Posts (Copper) MADE FOR NOMINAL WOOD POSTS. Product Dimensions: Each light measures 6" x 6" x 5.1", Base Dimensions: 3.63" x 3.63" Fits only on a nominal 4" x 4" wood post. This post cap is not designed for use on Plastic, Vinyl, or PVC posts! SOLAR POWERED - These post cap lights utilize the free natural power of the sun to operate. 4 crystalline solar panels absorb light during the day to recharge the 2 Ni-CD batteries (included) for use at night eliminating your need to swap out batteries or install a costly outdoor power system. DURABLE - GreenLighting takes pride in providing some of the highest quality products in the solar industry. These lights are no different and feature a durable copper plated frame and crystalline solar panel that have been designed to handle the outdoor elements for years to come. LED - Energy efficient lighting is now "in" and for good reason. LED's take 75% less power to operate compared to traditional incandescent lights while lasting up to 25 times longer. Overall the average life cycle of an LED bulb is rated to be over 100,000 hours! Each post cap light features 2 LED lights that emit a total output of 2.4 Lumens. QUICK SET UP - No more going to the store for last minute batteries. With all the items needed to get you going you won't need to run around to find those last minute parts. Each LED light comes with a (2) AA Ni-CD rechargeable batteries and mounting screws.