We at Center Enterprises manufacture 2 sizes of Wooden Geoboards. An 8" x 8" wooden geoboard and a 10" x 10" wooden geoboard. Our boards are durable, warp proof, and each has a 25 brass pin array. The 10" x 10" Circular Board has 29 pin array. They also have beveled edges and have a black acrylic surface to visually enhance the geometric patterns made on the boards.