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What would make a duffel bag "made for a macbook"? The one you linked doesn't seem to be made with special features for one. It showed a lot of Apple products on the right side that could be carried inside it. So I took that as the bag was large enough to hold such products.

Seems like you would just get a sleeve for your macbook and then put the two together into a duffel bag. Even then, it might not be as much protection as you need if you sling your bag around roughly.
 
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