Cotton Onesie, Heat Transfer Vinyl. This Custom Ordered Baby Onesie will keep your baby as snug as a bug in this soft 100% cotton. This bodysuit can be machine-washed and dried! The bodysuit also features a reinforced three-snap closure as well as double-stitched hems on neck, shoulders, sleeves and leg openings for extra comfort for the little one. These baby bodysuits make a great gift for a baby shower or new baby.