Adjusting the ports is the key to having the unit work correctly, but after that it works well. I keep mine running 24/7 and the catch pan is now only tramp oil (no coolant).
it works as it should. i have bad eyes and the old refractometer is hard for me to see. this is a fast and easy way to check machine coolant. down side it if you have dirty or oily coolant it doesnt always see it correctly.
This Aerator works 10x better than expected. Solved all of our coolant issues of poor circulation causing bacteria growth easily with installation of this aerator& the zebra skimmer.
I damaged the switch on our Zebra skimmer from HAAS, bought two and received them 4 days later. They even came with printed out instructions. Worked great.