Just finished these this evening. Based on a mid-1940's pattern for boys. This pair is at least two sizes too small for me, but it's a test piece. I should be able to draft a larger pattern based on the original. I'm pretty determined to get it right, and I'm excited about the possibility of having some long lasting boxers that won't have elastic to get worn out. The fabric is from a French cotton sheet that I bought at the thrift store.