The accordion in ONCE?

Very random question, I know, but you helped me track down the specific vintage synthesizer used in the SMILE promo recording, so I figured I'd ask.

I remember hearing somewhere that the musical ONCE uses a special make of accordion due to its light size and compact shape making it easy to act and dance around. Does anyone know what kind, brand, size or make this may be? I might have to pick up a stage accordion next year for an original show and I'd like to know what kind or specifications ONCE used, so I can find one with similar properties.

No, there's a small-sized piano accordion used too. She's playing a buttonbox concertina in the video, but I know at least on tour and during a few numbers on Broadway, it's a small piano accordion, which is more what I'm looking for.

Yup, confirmed that that's the one. They're a little more expensive than I had expected, but they're apparently top of the line for their weight of ten pounds.