I think “AirPods Max” would be singular. AirPods is the product line name. Max is the model. So you have AirPods, AirPods Pro, and AirPods Max. If you needed t

I think “AirPods Max” would be singular. AirPods is the product line name. Max is the model. So you have AirPods, AirPods Pro, and AirPods Max. If you needed to buy 10 of these you would say your were buying 10 pairs of AirPods, AirPods Pros, or AirPods Maxes. Honestly though, it's English we're dealing with, so there are more exceptions than rules, anyway. Muddy the waters further with proper nouns and branding considerations and basically the only people who can tell you what is "right" would be Apple's marketing dept.