The material is excellent. It is an interlock knit--a much thicker & softer cotton than the rib knit of the more popular Gerber and/or Carter's brands.
Unfortunately, these fit very poorly on my baby. The neck hole is much too large and even slides off of my baby's shoulders; however, it is so short that his belly peeks out. Imagine a loose fit shirt that rides up? I have had trouble with several of the Spasilk brand onesies & tshirts. I really want to like them because I do love the fabric quality but these just do not seem to work for my baby. I ordered 0-3mos and the neck hole could easily fit a 9-12mo old although it would be much too short. It was much too short for my newborn baby from day 1.