The instrument we have for daily lens cleaning, and are streak-free clean. Even stubborn dirt on a few metal parts came off at last. Operation is simple: fill with water, put the subject, press the start button, it takes 5 minutes and you can take out the clean items. Footprint as in a small saucepan. Apparently several ultrasonic cleaners are available that look very alike. The principle is probably always the same. There is probably no matter what brand you take. The rating applies only to the model Grundig, the other we did not try.
