The Carrier Transicold Line of Supra Diesel-Powered Truck Refrigeration Units offers cooling choices for small to large box trucks. The design reduces sound output by as much as three decibels relative to earlier models, making the Supra series especially well-suited for nighttime urban deliveries, the company says. Supra models S7, S8, and S9 provide solutions for trucks ranging from 10' to 28' in length and use 50 percent less refrigerant, providing greater cooling capacity than prior models. The Supra line features the company's APX control technology as well as integrates with their eSolutions telematics offering.