Review on Automotive Antifreeze Refractometer Windshield Measurement by Nick Brunner

Purchased to accurately measure the freezing point of the ethylene glycol coolant used in my laser systems. I needed a way to determine the freezing point without relying on approximate values from graphs found in search results. I've used specific gravity floats in the past, but didn't like that they were dense and helped carry previous contaminants into fresh coolant mixes. The device is very easy to use. It has a scale for mixtures of ethylene and propylene glycol with water and mixtures of sulfuric acid with aqueous electrolyte and (isopropanol?) with water for wiper fluids and is therefore very versatile. I can't say it's absolutely accurate, but I have to trust it to be close simply because there is so much scientific literature on ethylene glycol freezing points and the development of a scale, even if based on experience, isn't all that great would be difficult. The instrument appears to be well sealed so rinsing it thoroughly with slimy glycol after use is not a problem. Calibrating the device with deionized water is very easy with the included screwdriver. Two small plastic pipettes were also included, making sample collection very trivial. I think it was a good investment.