Joolz Geo 3 Upper Carseat Adaptor is available at Eurobaby.
Joolz Geo Upper Car Seat Adaptor Set - Eurobaby Online
Joolz Geo/Geo 2 Car Seat Adapters Adaptors for Maxi Cosi, Besafe, Kiddy and Nuna | eBay
Joolz upper car seat adapters for Britax Römer - Accessory | Britax Römer
Amazon.com : Joolz - Car Seat Adapters - Accessory for your Day Stollers - Great Flexibility - Keeps your Baby Sleeping - Compatible for Day2, Day3 and Day+ - Easy Installation & Fast to Remove : Baby
Joolz Geo Maxi Cosi Capsule Adaptor Set | Baby Zone