These truss rod covers are made of solid curly Koa and engraved with this beautiful design. We have numerous designs available and in different woods. These are the three hole designs made to fit Taylors with 3 hole truss rod covers. The edges are beveled and fit perfectly. There is a light coat of finish on them for protection and to enhance the beauty of the wood. The dimension of the holes are shown in one of the pictures for you to measure your instruments holes.