These car seat adapters have been designed for the Joolz Geo and Geo² are suitable for almost any infant car seat:
Joolz iZi Go Modular by BeSafe
BeSafe iZi Go Modular
Maxi-Cosi CabrioFix, Pebble & Pebble Plus
Kiddy Evo-Lunafix & Evolution Pro 2 (also in reclined position)
Cybex Aton, Aton 4, Aton 5, Cloud Q & Aton Q i-Size (also in reclined position)
Nuna Pipa