Sizing is true. This review is more about the bundle and not the mic or the interface (which both seem great). The short sleeves aid in keeping me cool and comfortable as I sleep. I really love that I do not have to have anything inside my ears and can still hear the music perfectly. Very original. (You will have to pair it once). It fit her airpods perfectly. ? Update 3/21/2021Major sound leakage! This was the perfect part we needed. I am 5?3 and 100-105 pounds usually an xs/small.