The Cisco CP-512G is deigned to only be used with the Cisco UC500 / UC520 series phone system.

Cisco IP CP-521G= VoIP phones only support the SCCP protocol at this time.

The Cisco Unified IP Phones 500 Series is a group of affordable, entry-level IP phones designed for use with Cisco's Unified Communications 500 Series for Small Business.

The Cisco CP-521G= phones are an excellent choice for customers undergoing the transition from traditional digital or hybrid key systems (KTS) and PBXs to a system based on the Cisco Unified Communication 500 Series. The Cisco Unified IP Phones 500 Series can easily be integrated into the Cisco Smart Business Communications System. They can be used in cubicles, retail settings, classrooms, breakrooms, lobbies, and manufacturing areas.

These phones are optimized to replace traditional voice systems, or to layer a next-generation voice solution into a Category 5 (CAT5) wired environment. The Cisco Unified IP Phone 521G is a single-line IP phone with two call line appearances. Four dynamic soft keys on each phone guide you through core business features and functions, while a backlit pixel-based display combines intuitive features, calling information, and device system information to give you information at your fingertips.

The phones are in line with Cisco Green, incorporating power efficiency features such as LCD shutoff to save power when the phone is not in use. This phone can also be used with productivity-enhancing features such as directory search and VoiceView Express.

Cisco UC520 (Unified Communications 500 Series VoIP Phones)

Reasons to buy from IP Phone Warehouse:

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