Heavy duty carriage buckle in traces, roller bolt style. Came with a new carriage harness from "Golden Saddlery" These are wider than Smucker harness and measure about 1-3/8"" Great chance to replace some badly worn traces for safety. These look good and should take a beating for marathon work. I didn't have a carriage that accommodated this type of trace, so had standard traces made for the harness. Hence they were never used.