SOLAR POWERED - These post cap lights utilize the free natural power of the sun to operate. A crystalline solar panel absorbs light during the day and recharges the Ni-CD battery (included) for use in the dark eliminating your need to swap out batteries or install a costly outdoor power system. 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 (1) AA Ni-CD rechargeable battery and mounting screws. 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! DURABLE - Reusable Revolution takes pride in providing some of the highest quality products in the solar industry. These lights are no different and feature a durable plastic frame and crystalline solar panel that have been designed to handle the outdoor elements for years to come. SIZING - Fits Vinyl and Wood Posts measuring 5" x 5" Add some light and style to your posts with these GreenLighting Solar Post Cap Lights for 5 & 6-inch posts. Designed for highlighting or marking your patio, deck, fence, or pathway, the GreenLighting Post Light emits an 18 Lumen output. The detachable bases are made to fit 5" x 5" and 6" x 6" posts while being securely fastened into place with the included screws. The 1.2V AA 700mAh Ni-Mh battery (included) is recharged by the natural power of the sun eliminating the need to install a costly landscape lighting system. A built-in light sensor detects the onset of nightfall or inclement weather to turn each light off and on automatically. It is recommended to install these post cap lights in an area that receives sunlight for 6 to 8 hours a day. Pack includes 8 post cap lights. Each light measures 7" x 7" x 4.7".