Left front of the stays. Someone, much later, sewed the front "belt" down. I really don't think it was meant to be like that since it looks like it was supposed to lace up, have an embroidered flap go from the right side, crossing to the left to cover the lacing. Then, it looks like, someone didn't like the idea of using pins and used a "belt" to keep the flap in place. Someone else, later, didn't like that or didn't understand the purpose and sewed the belt down.