Hi Would this be compatible with Maxi Cosi capsules and the Maxi Cosi ISO fix base? Thanks so much

Hi Olivia, thank you for your inquiry, the Diono Mats are unable to be used by other seats than Diono, however, I would suggest popping into your local store, or giving them a call, and they will be able to help you with an item that will work for you. I hope this helps