One set is "loose" fit, the other is "carpenter" fit. Both are 6-9 months, however, they were bought for my son when he was 9 months and 21 lbs, and they fit perfectly. He's 11 months now and about 25 lbs and they are just a little too snug. I hope that helps. I flat rate ship all of my items priority mail, neatly packaged and insured. If you win or purchase more of my items, I am happy to combine shipping for you. There are no smokers or pets in my home.