The LX-900-25 for Cisco models
SPA504G,SPA525G2,SPA509G,SPA508G,SPA502G,SPA501G and the SPA 300 SERIES
Is perfect for the telemarketer or Customer Service rep. With sound in Both ears, it helps reduce the amount of office noise you hear so you can better hear the call you are on.
for more information, please go here:
http://www.aiheadsets.com/LX-900-25.html