As mentioned Charlotte, I have rumgequält in advance with adapters of all kinds, only to realize in retrospect that I equal but this or a similar pump would have to buy. In any case, this pump do with the money exactly that for which it is intended: They pumped my Sitzball within about 50 seconds - and this without great effort. Clear ... completely wertig it does not act, but I am for the price and with a slightly wobbly plastic part satisfied as long as it fulfills its function and does not fall apart in the second or third pumping. And this third pumping process it has now left already behind him, moaning without coming to an end. One should in the use but still well pay a little careful not to pump too strong shear forces because the mechanism seems really cheap.
If the pump but give up the ghost prematurely, I will adjust my review in the way.
