These coolers are Made in the U.S.A.and manufactured by Specialty Auto Tech, Heat sink design has internal and external cooling fins to transfer heat and minimize the need for direct airflow. Sturdy welded aluminum construction withstands the toughest operating conditions such as flying road debris. Designed to work upto 3,000 P.S.I. and adds 1/2 quart to every foot of cooler length. These were designed with 1/4" and 3/8" npt female ports. Compact design is 3" in diameter and mounts in tight places. They are available in lengths from 12" to 48" long. Custom sizes are available upon request.. DISCONTINUED