Uppababy Vista Upper AdaptersThe Upper Adapters for VISTA allow you to easily convert your stroller into a double stroller. The upper adapters raises the toddler seat or MESA infant car seat (not compatible with other car seats) on your stroller to create more space between the primary and secondary seats. Quick, no tools attachment Color coded dot indicators to ensure proper installment Stroller folds with the adapters on Compatible with VISTA models 2015 later, Bassinet models