H&M thin cut-and-sew. Looks like it could be used as an undershirt. Set of 2, not sold separately. US 4-6 years old. Category size is listed as 110, but please check your child's usual size. No noticeable stains on the black one. The white one has no major stains, but I've included photos of any small spots I could find. Please excuse any folding wrinkles. Please understand these are used children's clothes. Shipping will be compressed.