Flat, smooth head eliminates the need for a washer Orderd bolts washers and nuts all from Hillman and at 13-15 inlbs, that's INCH POUNDS, exactly 25% of the bolts stripped threads. $35 worth of trash. Lesson learned These stainless steel carriage bolts are designed to fasten a wooden face to either a wood or metal frame. 3490 | Bolt Assembly: 1/4-20 x .375 Black SHCS and Roll-In T-Nut with Carriage Bolts 3490 1/4-20 By 3/4-Inch Stainless Steel Carriage Bolt, 10-Pack Square Neck Self-locking Bolts Carriage bolts are designed to fasten a wooden face to either wood or metal. Hillman 3492 Stainless Steel Carriage Bolt 1/4-20 x 1-1/4 Inch, 10-Pack The square underside of the head is self locking to eliminate spinning and the need for a driving tool. Its smooth, rounded head is designed to eliminate the need for a washer and provide a semi-flush finish to applications.
