The bag’s finished dimensions are 36 inches long, 21 inches wide (laid flat), 13 inches wide diameter with grommets about 1 1/8 inches. Note that these are finished dimensions and do not include any seam allowances. Several people have remarked that the bag seems “small” to them. Not having seen a number of original bags, it is hard to estimate whether this specimen is small or not. It is certainly smaller than a modern sea bag as usually encountered. It is in remarkably fine condition. It shows little use. Perhaps it was too small when it was finished and was set aside. If you have pictures and dimensions of an original, please share.