Audicom 2.5mm Call Center Headset Headphone with Mic and Quick Disconnect for Cisco Linksys SPA SPA921 SPA922 SPA941 SPA942 SPA962 303 501G 502G 504G 508G 509G 525G Telephone IP Phones (H300QD25A) Direct connect over-the-head headset headphone, No additional amplifiers or adapters required, Most easy setup headset solution. Super Lightweight, Super Durable Headset with Comfortable ear and mic cushions. Superior quality sound with the flexible adjustable noise cancellation microphone. NO Mic Mute / Volume Control built in. ONLY PURCHASE IF YOU HAVE ONE OF THE PHONE MODELS LISTED BELOW IN DESCRIPTION, CHECK OUR STORE FOR HEADSETS FOR OTHER PHONE MODELS OR CONTACT US FOR COMPATIBILITY GUIDE!