These lower adapters allow you to attach a bassinet, Mesa Infant Car Seat or RumbleSeat V2+ (all sold separately) to the UPPAbaby Vista as a secondary seat. Compatible with Bassinet, Mesa Infant Car Seat and RumbleSeat V2+ with Vista and Vista V2 strollers(all sold separately) Large hubs ensure quick, no-tool attachment Color-coded dot indicators to ensure proper installment Stroller (sold separately) folds with the adapters on Easy open-and-close mechanism with closure lock for ease of mind Plastic Imported