Under Armour Heat Gear Shirt Boys Youth, Red

Boys under armour shirt. Tag/Size is worn off. It’s my son’s shirt. I’m guessing it’s a medium. Here are the measurements: 23” long 18” wide Smoke free, pet friendly home. Other than the sizing information on the inside being worn out, the shirt is is very nice condition. See pictures. Let me know if you have any questions. Thank you.