Rolf Prima Tandem rims are 31 mm deep. Borrowed a tube with 48 mm valve stem, after a second flat.
It was not long enough to work with the C02 inflater we had, but just long enough to work with a Road Morph pump. I'd go with a 60mm.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.