Featuring a free-flowing 4 and 6 pass cooler in one compact package and fabricated of 1/2 inch copper tubing and aluminum cooling fins, this Made in the USA Dual-cirucit cooler includes 2 each 11/32 inch and 2 each 1/2 inch barb inlets. It provides heat transfer capabilities for two independent systems such as engine and transmission or transmission and power steering that competitive units just can feett match at anywhere near the price.