... Cleaner (1) Lowest back-repair rate (2) Safe (3) 3L,4L,5L,6L,10L,22L,33L ... . Ultrasonic Cleaner:(1) Lowest back-repair rate(2) Safe(3) 3L,4L,5L,6L,10L,22L,33L and ... and the soiling.They are often employed for cleaning of jewellery, lenses and other optical parts, coins, watches, ... or other solvents can be used, depending on the type ofcontamination and the workpiece. Contaminants can include dust, dirt ...