OWT Thru-Bolts Another Amazing Building Breakthrough!! OZCO?s Ornamental Wood Ties (OWT) Timber Bolts are an innovation in structural design. OWT Timber Bolt will replace standard thread-all, carriage or similar through bolt fasteners while helping you finish projects faster, with a more professional look and strength. The revolutionary heavy duty OWT Timber Bolts come in both ?? and ?? diameters and five different lengths, from 2? all the way to 12?, making them perfect for any wood-to-wood projects and designed to eliminate trimming of unsightly and potentially dangerous bolt ends. OWT Timber Bolt?s 3/8? hex washer head design combined with innovative compression technology that inserts like a traditional bolt and tightens from the inside out. The corrosion resistant Coating and Materials combine for long lasting performance and are approved for ACQ Treated Lumber projects. The Hex Cap Nut design prevents the outside coating from being marred or damaged. While all of our OWT Building Products are designed for exterior projects they are #OWTstanding for interior design, from architecture to furnishings.