Photo credit: RTI
RTI's VFT-1 (Vehicle Fluid Tester), a digital refractometer, can test the freezing point of glycol based coolants. By adding a few drops of coolant to the test surface and pressing the "Go" button a couple seconds later the VFT-1 gives a digital readout of the freezing point. A chart typically located on a coolant bottle's rear label, illustrates that the lower a freeze point of coolant, the higher the boiling point of the engine coolant. Additionally, the VFT-1 can also test for percent of water present in DOT 3 brake fluid, battery acids specific gravity and DEF Urea percent weight in diesel exhaust fluid.