Honeywell Home CT410A White 24V Manual Thermostat. Dimensions: 2.75"W x 1.5"D x 4.5"H. Compatible with most 24V heating and cooling systems including gas, oil, and electric forced-air systems. Features a simple manual dial design with no batteries required. Item is in like new condition and includes original box. No damage or missing components noted. Model: CT410A.