If I create a SAFE on Base does that SAFE only accept Base tokens? I think the answer is yes but just want to confirm

One workaround to this usability problem (e.g. someone sending the wrong token to the SAFE) is to give the wallet a @basename 

That way it is unequivocally associated with the L2 and marginally reduces the risk of someone sending non-Base tokens to that address - not perfect, but better than a vanilla ENS

Web3 naming (.base) for the next billion+ users on BASE | Native Name Service | http://basename.app

ENS supports setting a Base-specific address! I've set it on gregskril.eth as an example https://app.ens.domains/gregskril.eth

though I'll admit wallet support isn't near where it should be yet... working on it

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I like building apps on web3 protocols. DevRel @ ENS Labs. gregskril.com

Yes saw that! Thing I'm unclear about is is it possible to ONLY set a Base address and not have any other address associated with the ENS?

The issue with a SAFE that's restricted to a single L2 is you really don't want someone to accidentally send the wrong token to that address — my OtoCo safe can't receive mainnet