Is it only compatible with maxi cosi car seat?
Hi, Audrey,
No, with those Maxi-Cosi car seats, you can also attach Cybex, Joie, Nuna, Recaro and Kiddy car seats s the attachment systems are the same. I would definitely go fo lighter, smaller car seats though as something huge like the Cybex Cloud might be a tight fit (though it could fit, just saying).
Your -very berry- Eli.