I have a couple of carriers and what I look for is room for the pup to stand upright and to be able to fully turn around and room to just lay and be comfy which doesn't take a lot of room because they just curl into a ball!
I am going to order the black Chien carrier from Petsmart. it looks like it will be roomy enough for a 3lb pup. (I have a feeling Chewy is now close to 3lbs
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