Package includes baby jogger city select stroller baby jogger city select additional seat unit the baby jogger city select isa one of a kind multi funtional stroller that allows parents to mix and match seats carrycots and car seats to customise their stroller the baby jogger city select starts with a single capacity stroller but expands to a double by using a unique patented attachment method as your family grows simply snap on a second seat and youre ready to take on the town in the sty