I have a 30" and that is reccommended for a cocker
But both mine also have a 36" crate each with a single duvet in (spoilt cockers

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i also cover half off it over with a blanket to make it more den like and they both love their crates

I would say chewie is fine to introduce the crate too, just make sure you follow the simple steps and do it over time
Feed them in crate with door open to start with - a good book on how to introduce the crate is Pamela Dennison's An idiots guide to positive dog training (well worth the money @ £15 as has loads of stuff in there

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