Convenient In-line Controls: Convenient inline volume and mute controls allows a more flexible listening experience. 5.4ft long cord offers flexibility to move around,designed to keep pace with the demands of work and life. Ultra Durable: Precision design, quality plastics, unibody headband construction, metal mic boom joints makes this call center headset sturdier and more durable. You can even pull or bend the headband for personal optimal fit. Most Comfortable: Super lightweight office telephone RJ headset with adjustable headband to fit all head sizes, high quality and soft leatherette ear cushion enhance all-day wearing comfort. Compete with Plantronics or Jabra heavy duty Phone Headsets for Call Center, Telemarketing & Office. HD Voice for Clear Communication: Wideband Sound telephone headset enables natural listening experience, noise canceling microphone provides greater focus and concentration by blocking background noise, plus acoustic Shock Protection to protect your hearing. Less noise, Clearer voice. ONLY COMPATIBLE with Yealink T19P T20P T21P T22P T26P T28P T41P T23G T32G T38G T40G T42S T46S T48S Avaya 1608 1616 9608G 9611G 9620 9630 9640 9641G 9650 J139 J169 Grandsteam GXP 1400 1405 1610 1615 1620 1630 2000 2120 2124 2135 2170 280 285 GXV 3005 3006 3240 3275 Snom 300 320 360 710 821 870 Panasonic KXT 2260 7220 7330 7420 7433 7665 7740 Zultys ZIP 36G 37G 33i 35i AltiGen IP805 Aastra 6737i and more deskphones listed in description.