Voistek Call Center Telephone Headset for Polycom IP Phone 300 301 335 430 450 501 550 560 600 601 650 670 CX300 CX500 CX600 VVX400 VVX500 VVX600 VVX1500 Shoretel 420 480 480G 485 and Altigen 500 510 600 705 710 720 Digium IP D40 D45 D50 D70 and Aastra models 6731i 6735i 6737i 7446i 9112i 9133i 9116 9143i and 9480i See Compatible Phone List (PARTIAL) in Description, DO NOT BUY IF YOU CAN NOT FIND YOUR PHONE MODEL IN LIST, CONTACT US FOR COMPATIBILITY GUIDE ON YOUR SPECIFIC TELEPHONE MODEL IF NEEDED. Direct connect over the head RJ headset,no additional amplifiers or adapters required, most easy setup HANDS FREE headset solution for Most Standard Telephones Equipped with Modular RJ Headset Port. Superior Call Center quality headset FOR DESK PHONE, excellent sound quality, lightweight, durable and comfortable for all day use Noise canceling microphone to reduce background noise and Acoustic Shock Protection circuit to protect your hearing. A LANDLINE TELEPHONE HEADSET WITH Flexible goose neck boom,adjustable headband,Extra comfortable leatherette ear pad, Shirt clips included, NO Mute / Volume Control built in.