This Mastertrol zone panel control plug-in relay, model number 04CL-RD, is a must-have for businesses and individuals in need of HVAC and refrigeration equipment. Its reliable performance and quality make it the perfect addition to your collection. Ideal for use in Other HVAC & Refrigeration industries, this Trol-a-Temp Zone Panel Control Plug-In Relay FRL263a024/04CL-RD is a great investment that guarantees satisfaction. Its compatibility with a wide range of equipment and HVAC systems make it a versatile choice for anyone looking to buy HVAC equipment.