Made from a solid piece of white oak. These hold a 4" test tube (comes with the vase). Can be hung with either double sided tape, or with a #8 wood screw though the pre drilled hole. These are 1.5" thick, and each of the shorter sides are 3" long. I dyed these with my own mixture of dye and finished with a coat of clear. The grain on this wood is tight and neat. You can tell it was not grown on a tree farm. This tree fell in town, and a friend cut it into planks for us. The wood is beautiful. Pictures do not truly show its beauty.