The KirmussAudio Model KA-RC-1revolutionizes the way we clean records! First and foremost; the Patented record suspension system assures that the grooves of records of all sizes (7", 10" or 12") are cleaned safely. We do not use skewers that have been prone and known to damage the record labels. We do not use a frequency higher than 35 kHz as this is the "sweet spot" which won't damage the grooves. Our "bath" (which comprises of 6L of distilled water with a maximum of 40 mL (1.4 oz) of ISA 70% solution) only heats up to 95 degrees Farhenheit... Again, these have all been measured to optimize record cleaning and restoration while being SAFE for your vinyl. We apply an anti-bacterial surfactant (supplied with the machine) by way of a goat hair brush (also supplied with the unit) onto to the record. Ultrasonics need a surfactant to aid in the cavitation of the water solution to better clean and remove contaminants. It is also an anti fungal agent which is another common issue with older LP's. Our machines are SAFE and bear the ETL's rubber stamp (ETL tests products to UL, CSA and CE standards).