Catherine: So sorry, never mailed a singlet. We have only Large, not extra large, or XL tech tees. I can bring them on Sunday and you can chose one on your way to Staten Island (plus he can wear it to run in)!! My advise about clothingM Pack in the bag they give you at the expo what you want to put on after the marathon (you will pick it up near the finish line). But bring old sweats or something you don't mind getting rid of after you start running--you'll be out there waiting for a long time after you've checked your bag so you will need something to keep warm in the meantime. The Verrazano bridge and beyond is strewn with abandoned clothing that gets delivered to charity organizations...hope this helps.