[Applicable Size ]- APONUO solar post cap lights measures 5.71x5.71x2.76 inches, comes with screw fittings and 3 different sizes of bases. You can mount the 4x4 post solar lights on 4x4,6x6 (actual 3.5x3.5,5.5x5.5) inches wooden post caps,or you can mount aponuo 4x4 solar post cap lights on 4x4 (actual 4x4) inches vinyl/plastic post caps. Note:Does not fit actual size 4x4 wood post caps,5x5 vinyl post caps. [Warm White/Cool White]- The fence post solar lights have 2 color modes, warm white(3000K) and cool white(6500K). APONUO post lights outdoor 4x4 solar with 10 led beads is capable of emitting 15 lumens of bright light at the start of dusk automatically, making it perfect for outdoor lighting and garden decor,deck decor,fence decor,patio decor. [Solar Post Lights Outdoor Waterproof 4x4] - APONUO solar fence post lights are made of high quality pp plastic, which can resist pressure and water, with a waterproof rating of ip44, sealed well and will not rust, ensuring that the post