Swivel hinge unit rotates 180 degrees. Each arm moves independently. Plug in units. Very simple to install. Energy efficient. Integrated on and off switch with pilot light, located at the bottom of vertical bar. No liquid in unit. Standard voltage: 110 volts. Power: 72 Watt. BTU: 245.52. AMP: 0.65. Average temperature range: Up to 136 degree Fahrenheit. Made from stainless steel. 25 in. W x 3.9 in. D x 37 in. H (9 lbs.). Warranty. Assembly instruction.