The Guardian Electric A420-066663-00 is a medium-duty Plug-In Transformer that is used to convert 120 volts AC to 12 or 24 volts AC. This transformer is UL and CSA approved and features a power rating of 120 VA and circuit protection of 15 amps. It is enclosed in a 2" x 3" inch plastic enclosure with a mounting bracket. The transformer is ideal for applications such as lighting systems, alarms, door openers, security systems, and industrial control equipment.