These car seats are compatible with the Baby Jogger City Mini 2 Double and City Mini GT 2 Double strollers using an adapter:
Please note these adapters are not compatible with the 2019 and earlier City Mini Double or City Mini GT Double strollers.
The double stroller holds only one car seat; it does not hold two car seats for twins.
The car seat adapters for the single and double versions of the City Mini 2 and City Mini GT 2 are not interchangeable. See Car Seats Compatible with the City Mini 2/City Mini GT 2 Single Stroller.