The Keystone 8,000 BTU 115V through-the-wall air conditioner with 4,200 BTU Supplemental Heat Capability is perfect for rooms up to 350 square feet. In addition to cooling, this versatile unit also offers supplemental heat capability, providing you with an additional heat source to your main heat source when outdoor temperatures are above 45 degrees Fahrenheit. It has electronic controls with LED display and a temperature sensing LCD remote control allowing you to conveniently see, set and maintain the room temperature from across the room. Money saving features include energy saver mode, sleep mode and a programmable 24-hour timer. Plus, quiet operation (51.8 dB on low) helps you get a good night's sleep. This unit is designed for through-the-wall installation and is not designed for standard window installation (WALL SLEEVE SOLD SEPARATELY).