Westinghouse Pagoda II Solar LED Post Cap Light for 4 x 4 Wood Posts (White, 6 Pack) Interior base measures 3.88" x 3.88", rail adapter interior measures 3.5" x 3.5".Each light measures 5.94" x 5.94" x 4.75" Durable weather resistant plastic construction will handle the outdoors with ease Bright white LED bulb is powered by the included 600mAh Ni-Cd battery Solar panels will absorb sunlight regardless of cloud cover Pack includes 6 Post Cap Lights. Interior base measures 3.88" x 3.88", rail adapter interior measures 3.5" x 3.5".Each light measures 5.94" x 5.94" x 4.75"