iGlow 18 Pack Copper Outdoor Garden 4 x 4 Solar LED Post Deck Cap Square Fence Light Landscape PVC Vinyl Wood Bronze 1 Ultra Bright White LED. Last up to 100,000 hours. Pre-installed Rechargeable AA Battery, Last up to 2 Years Before Replacing. Automatic Sensor Activates at Dusk with NEW and IMPROVED Solar Panel for Superior Charging Performance Weatherproof  Designed to Protect the Lights from Natural Elements. Easy to Install. No Wiring Required. All Fence Post Attachments and Parts are Included. Dimensions: 5.75 (L) x 5.75" (W) x 4.5 (H). Base Dimensions: 4" (L) x 4" (W). Post Size Fitting: For Wood or Composite Posts, The Post Size Must Be Smaller Than 3-13/16" Square. For Hollow Vinyl Posts, the Inside Opening of the Post must be Larger than 3-15/16". These Post Caps are NOT designed for use on SOLID PVC / Vinyl Posts that are EXACTLY 4" x 4". (Tips: Please Measure your Posts before Purchase)