If you expect to see some heavy hitting robot on robot action this year, these bumper boards have a well developed bumper wood joint that will hold together through the impacts. The bumper boards are CNC routed Baltic Birch, 18 layer, super straight, 3/4" plywood. They have an interlocking pattern that allow for alternating screws and large wood glue surface area. Full bumper wood kits include Titebond II wood glue, and 24 #6 1-5/8" wood screws. Bumper wood is sized for an inner square of 30.25 x 30.25", leaving room for tucking in fabric on a 30x30" robot frame. Smaller bumper board sizes available to make frames with sides of 28x28", 26x26", and 24x24". These also have the same extra gap for tucking in fabric. Order the required single pieces to make rectangular frame robots. If you order 4 or more single board the glue and screws will be included.