Our fabrication tables are cut on a very high end laser, with a tolerance of +/- .005 creating the flattest and most reliable fixture block style welding bench on the Etsy marketplace. Varying sizes available upon request.The rib frame is 8" deep/tall on the larger tables, and 6" on the smaller tables. This robust rib skeleton creates the rigidity and flatness required for the flattest, and most resilient table you could ever need. 5/8 holes, spaced 2" on center. Standard fixture table clamp