External Dishwasher Softener for hard water. Comes with 2 of 10"x2.5" Resin Softener Cartridges. 3/8" thread or 1/2" thread connection Unique Single stage External Water Softener system for dish washing machines: no more spots on your dishes and glassware, normally installed on In-line before Dishwasher fit under any sink, handle up to 100 F Degree instantly transforms hard water into soft water. Removes calcium, magnesium, iron and other hard minerals Housing color: blue