OsoCozy bleached prefolds are twill weave cloth diapers (Also called gauze). They start out incredibly soft and absorbent, and they become even softer with washing. Wash these cloth diapers a few times in hot water, and they fluff up beautifully! As with all cloth prefolds these will shrink 5-10%. OsoCozy Prefolds are 100% Cotton - Unlike prefolds from more recognized national children's clothing brands which use a synthetic polyester filling between just two layers of cotton. Our diapers are a better value as they are thicker and more absorbent. Additionally, there is often an ammonia odor buildup in synthetics which you won't get in cotton diapers. Two Basic Sizes - We offer eight sizes in the bleached prefolds but most families need just two sizes. Those two sizes are the Infant 4x8x4 for 7-15 lbs and the Premium 4x8x4 for 15-30 lbs. Don't be fooled by "One-Size" prefolds which will be bulky on newborns and have insufficient absorbency on larger babies.