Glvaner (10 Sets) 1/4-20 x 3/4" Stainless Steel Carriage Bolts Screws Round Head Square Neck and Hex Nuts & Flat Washers 304 Stainless Steel 18-8 Full Thread Coverage

Carriage bolts have a dome shaped head and a square neck generally requiring a hex nut and flat washer.

The square neck makes them self-locking when used within a square hole.

The smooth, domed head provides a semi-flush finish.

Drill a hole in the surface material that matches the diameter of the fastener, insert the bolt, and connect the nut on the other end.