The Onya Baby Infant to Toddler bundle is the whole enchilada. With this package you can use your Onya Carrier from newborn on. Our Baby Booster infant insert securely snaps into your Onya Baby Carrier and allows you to adjust the boost as your baby grows. Also in the bundle is our Chewie teething pads, designed so they cant slide up the strap and stays put. They also have a water resistant backing, so your carrier stays spiffy and dry. Each ergonomic baby carrier is constructed of rip-stop nylon with air-mesh lining and has our patented, innovative hidden seat built right in. So as long as there is a chair with a back nearby, youll never be caught without a seat for your little one again. With the Infant to Toddler bundle your ready to go, right from the start!