Aprilaire® Control Panel with LCD Display, 18 - 30 VAC, 18 V-A at 158 deg F, 30 V-A at 90 deg F Damper Output per Zone, 18 V-A at 158 deg F, 30 V-A at 90 deg F Panel and Thermostats VA, 50/60 Hz, 4 -Zone, 5 - 90% RH Non-Condensing Humidity, 32 - 158 deg F, 1.86 in L x 8.85 in W x 14.72 in H