Not sure about any pun, but what you see on the last panel next to Jucika is an old weighing machine combined with a height scale (the tall measured part), similar to this vintage one.
So my guess is after dancing with a much shorter, and much taller man, Jucika has set an exact height scale for her next dancing partner. 🤷♂️
Oh, ok, I misunderstood why they were asking for the pun.