The models have only one unit system: °F. With the indication we may know the freezing point of either ethylene glycol or propylene glycol based cooling systems.
TRZ 4in1 Antifreeze Refractometer Ethylene Glycol, Propylene Glycol in Antifr...
TRZ 4-in-1 Antifreeze Refractometer Ethylene Glycol, Propylene Glycol black
TRZ 4-in-1 Refractometer Ethylene Glycol, Propylene Glycol in 18cmXD35, Black
