Edwards, 596, Class 2 Transformer Hardwired 6 VAC, 10VA; 12 VAC, 15VA; 18 VAC, 15VA POWER SUPPLY, Non-regenerative thermal overload protection, Grounding wire, Pre-stripped pigtails, Screw terminal connections on secondary, Edwards 590 Series Class 2 Signaling Transformers are easy to install, low voltage power sources for residential, commercial, and industrial uses. Mounts in a standard 1/2" (13mm) knockout or surface mounts using the provided foot mounts. These transformers are suitable for mounting in both plastic and metal back boxes. May also be used with the Cat. No. 593 transformer plate for enclosed mounting in a standard two gang outlet box. The 596 transformer is used in light duty applications. It is ideal for standard doorbells and chimes in residential and commercial applications. Multiple secondary voltages expand possible usage.