This Large Cat Pod has the same heating system as our more expensive Handcrafted Houses. It consists of a 50 watt infrared heat lamp screwed into a recessed light fixture so it is out of Kitty's way. There is an adjustable thermostat that you can set and forget. The heat only comes on when needed, also has a 20 ft cord. These coolers are very well insulated and hold the heat in very well. Made from an Igloo or Coleman 70 qt cooler Pod measures 25" x 13" x 13" deep on the inside. Will fit one Large Cat or 2 average size cats that are willing to curl up together. The 2 large doors fit the biggest cat and the opening measures 7"x8". There is a Cat Pad Bed on the floor for even more warmth and comfort.