6 Pack Solar Square Outdoor White LED Fence Post Cap Light for 6x6 Posts with Wood Post Adapter Rechargeable Battery included (3.2V 300mAh Li-ion) 100% Solar Powered no external wiring necessary 5 White LED's Per Light, 78 Lumens The 6x6 model number PL248 have two sides and will serves multiple functions. Inside diameter of one side is 5.75" (good for wood/composite posts) and inside diameter of other side is 6 1/16" (good for PVC/Plastic/Vinyl posts) Solid/Hollow. Optional 5 x 5 Base Adapter Included!