An extra Car Seat Base G2 expands the functionality of your Orbit Baby travel system. This base also adds the convenient and back-saving dock-and-rotate functionality to your Toddler Car Seat. The Car Seat Base G2 works with all Orbit Baby car seats, for rear-facing usage. This product is also included in both the Infant Car Seat + Car Seat Base G2 package, and the Stroller Travel System G2 package.