The Unison DR6 120V dimming rack is a useful device. However, please note that it doesn't come with a key to lock the door shut.

To use the Unison DR6 120V dimming rack, first make sure it's properly connected to a 120V power source. When operating, adjust the dimming settings as per your lighting needs. As a heads - up, since it doesn't have a key for the door, you might need to find an alternative way to secure it if necessary. For maintenance, keep it in a dry and clean place. Regularly check the connections to ensure they are tight and free from damage. If you notice any issues, it's best to consult a professional.