Butterfly Table: Slab Dining Table: Giancarlo Studio Furniture: The book matched boards used for every Slab Dining Table top are truly one in a million. The boards go through a very exacting selection process based on grain structure, beauty, width, thickness, and cut. Once the boards are selected they are joined and fitted with two full thickness butterfly keys. There are no screws, nails, or glue used in the construction of the Slab Dining Table. The top of the Slab Dining Table is held together by the Butterfly Keys only. Each Butterfly Key provides six thousand pounds of compressive force to hold the two book matched slabs evenly and perfectly together. Do not be fooled by simple surface butterflies. They are aesthetic only. These butterflies are the full thickness of the table and give the table its core strength and stability.