The potentiometers are larger than others sold e.g. by RobotDyn, but they feel of worse quality. They move within a range of almost 75mm with a light, but noticable noise. The smoothness does not feel equal even between the two on the same board. Size of the module is 117x39mm. The shaft reaches to 25mm height - counted from the bottom of the board (1.5mm thick). With the buttons the total height is about 28mm (add another 1.5mm for contacts on the bottom of the board).
Minor correction: the range of the potentiometer is actually only about 66mm. So it is almost exactly equal to the smaller potentiometers. Sorry for wrong measurement.
1 slider has nearly no friction. The other slider has a lot of friction. Except when moving it up and down for a couple times really fast. Then it also has no friction for a little while.