TOSLink Input - Probably a dumb question

just acquired a Direct Stream and am swapping over inputs from my old DAC. Is the optical TOSLink a standard or mini connector? I can’t get my existing standard connector to fit (and don’t want to force it.) It’s a pre-used existing cable and, yes, I’ve removed the protector covers already.

Standard - The first few times you use it, it is tight.

Thanks Ted, seems the plug was mostly at fault, possibly a little oversize coupled with the initial tight fit? Solved with a new, short cable linked by connector to the old one.