The waist of this swaddle is tightened to give the baby a slight sense of restraint making the baby feel as safe as in the mother womb. The loose bottom allows the baby legs to maintain natural curvature for healthy development. The two way zipper lets you change diapers without taking off the swaddle completely just unzip the bottom which is very convenient and keeps the baby warm during the change. Our infant swaddle is made of cotton which is very friendly to the baby skin. When the cuffs are closed babies can touch their face through the sleep bag swaddle to self soothe preventing their nails from scratching their face. Opening the cuffs can help babies from swaddle to wearable blanket. This baby swaddle sleeping bag adopts novel colors and patterns and can be chosen according to the age of your baby and your preferences.