The Crosstown Slim All-in-One Convertible Car Seat is made to be with you for years, comfortably fitting your little one from birth to 10 years with 3 modes of use: rear-facing (540 lbs., 19 inch40 inch), forward-facing harness (3065 lbs., 34.4 inch49 inch), and belt-positioning ...The Crosstown Slim All-in-One Convertible Car Seat is made to be with you for years, comfortably fitting your little one from birth to 10 years with 3 modes of use: rear-facing (540 lbs., 19 inch40 inch), forward-facing harness (3065 lbs., 34.4 inch49 inch), and belt-positioning booster (40100 lbs., 43.4 inch52 inch). Its ultra-slim 17 inch design is a space-saver youll welcome as it allows for 3 across the back seat of most cars. The 1-hand adjustable harness and 8-position headrest ensure the proper fit and keep your little one comfy, all without the need to rethread the harness during adjustments.