The first thing about ultrasonic Cleaners is the Transducer. You can
get machines with these made in China, Taiwan, US and German. As a
package made for small Jewelers the German Elma Machine is one of
the best. You should be able to find someone in Tel Aviv that carries
this in 220 V the Quart size (LC20H) is good for a small store.
The heat switch is good to have you could warm up before you start
Elma makes good transducers , has all stainless tank and case, they
use a quality timer switch. Their warranty service and track record
is good. Well, I think I have covered the whole machine.
Regards Kenneth Singh