This power adapter from Cisco is designed for North American use and is compatible with the 7921G model. It has a black color and was manufactured in China. The adapter is ideal for use with VoIP business phones and IP PBX systems, and can be found in the Computers/Tablets & Networking and Enterprise Networking, Servers categories. With this item, you can power your device without worrying about compatibility or electrical specifications. Get the job done with confidence using this reliable power supply.