Lord, even an Italian ought to be able to google "film slosher", like I said to. If you had, the first choice given would have shown a picture of Steve Peterson's six negative slosher.
Originally Posted by MarcoGiardini
The advantage of them is that the negatives stay untouched as you move them from tray to tray and you can process 1 to 6 negatives without having to stack them or handle them in any way. It is very useful for N+ or N- development, where you have only a small number of negatives to be developed differently and the process is relatively random for even development of the negative. You just agitate by a pumping up and down motion in the tray alternated with a repetitive motion similar to a priest's signing of the cross, using the "Dominus" motion several times and, then, skipping the Dominus bit and only doing the "Vobiscum" part several times.