Tree rings manufactured by TerraCast® Products. A Tree Ring is a light fixture that is designed to attach to a tree by encircling the trunk or a branch. It usually accommodates up to six lights that can be pointed in varying degrees of rotation. Tree rings are a must-have for landscape lighting designs. Our Tree Ring is a very unique product. There are a few other manufacturers who make tree rings, but none of them are made out of Resin. Resin Tree Rings are an innovative product that no one else in the world offers. We offer these resin Tree Rings in 2 different sizes: 18 inch and 24 inch diameter but are also available on special request in 32 inch diameter.