With reliable air conditioning units, Keystone produces consistent cooling to keep you comfortable, even on the hottest days. Installed easily through-the-wall, this 8,000 BTU / 4,200 BTU supplemental heating capacity air conditioning unit can effectively cool rooms up to 350 square feet and also acts as a heater on chillier days. Supplemental Heating mode is meant to be operated when temperatures outside are between 23 and 76 degrees. This mode is supplemental and NOT meant as a primary heat source. With dehumidification up to 2.1 pints per hour to remove moisture from the air, this unit is perfect for smaller-sized living spaces like apartments, dorm rooms, sheds, and much more. The unit features a unique remote with a thermostat built in to sense the temperature of the room, displays it on the remote's LCD screen, and sends a signal to your AC unit every 3 minutes for accurate cooling. Money saving features include energy saver mode, sleep mode, and a programmable 24-hour timer. You'll know when it's time to easily remove and clean the mesh filter with the Check Filter alert. Keystone not only provides a 1-year warranty but ensures that you stay cool and comfortable at a cost-conscious price.