It's a simple tap on "strozzo" that can be useful when water the garden for not wasting water. it is simple to build, super cheap (I used all waste material and as such can be constructed by anyone with a little handworks and at no cost.
1)handle released: through the elastic back the tube remains throttled and the water does not pass.
2)handle pressed: the bottleneck opens the water flows
Finally, it is sufficient to refine the pieces with sandpaper finish to remove any smudges and assemble all. In particular, one or more flexible will be put into the core of the system and the other two elastic as handle backwards. We must then pass the tube appropriately and calibrate the loop so that functions properly into. This stage will require some time to refine the closure and get the best possible compromise (will not be able to claim a perfect closure, is always an emergency device).
I thank all those who have followed up to here, and ... If you please vote for me, or possibly commented constructively.
To the next.