The OHMITE RHS15KE is a wirewound rheostat, a type of variable resistor used for controlling electrical power. These rheostats are electro-mechanical devices, meaning they are subject to mechanical wear and have a finite lifespan. They are commonly used in applications requiring adjustable resistance, such as motor speed control, lighting dimming, and volume adjustment. Models H, J, G, K, L and N are listed under UL File No. E-10946 and CSA File No. 21309. All rheostats have a 10% tolerance.