Relative Accuracy Testing is required to insure that continuous monitoring systems are providing accurate data. The StackTuff™ Test Umbilical is designed to provide long, trouble-free service in portable CEMS testing operations. Stack-Tuff lines are produced in standard 25, 50, 75 and 100 foot lengths. These lines are specifically designed to provide fast heat-up even at low ambient temperatures of –20°F [-4°C]. Stack-Tuff’s unique integral draw system allows safe lifting without internal or external damage to the sample line.