OZCO Ornamental Wood Ties (OWT) 2 in. Heavy Duty Timber Bolt Washer (150PK) is used as an accessory for Hex Cap Nuts, Timber Bolts, or Dome Cap Nuts on pergolas, arbors, gazebos, or where extra enforcement and impact is needed. A 6-gauge thickness gives depth and rugged style to your projects and optimizes the bolt’s strength on timber connections.