This 2.5mm telephone headset works with most Panasonic office phone. Whether you work in an office or call center, the headset will fit your needs. Headset with microphone makes your hands free when on the phone and to be able to work on the computer during conference calls, also it saves you from neck pain. This 2.5mm phone headset blends lightweight design with durable construction for all day wearing comfort and lasting performance. With wideband audio technology and industry-leading noise cancelling microphone, the corded telephone headset delivers crystal clear sound in busy contact centers and offices. 2.5mm Headset Compatibility (Included but not limited) Cisco: Cisco SPA 303, SPA 501G, SPA502G, SPA504G, SPA508G, SPA509G, SPA512G, SPA514G, SPA525G, SPA525G2. SPA921, SPA922, SPA941, SPA942, SPA962 Panasonic: KX-NT136, KX-NT343, KX-NT346, KX-NT366, KX-NT543, KX-NT546, KX-NT551, KX-NT553, KT-NT554, KX-NT556, KX-NT560, KX-T7603, KX-T7625, KX-T7630, KX-T7633, KX-T7636, KX-T7668, KX-T7730, KX-T7731, KX-T7735, KX-DT321, KX-DT333, KX-DT343, KX-DT346, KX-DT521, KX-DT543, KX-DT546, KX-TNT136, KX-TPA65, KX-TS Series, KX-UT113, KX-UT123, KX-UT133, KX-UT136, KX-UT248, KX-UT670, KX-TG6511, KX-TG6512, KX-TG6513, KX-TG6531, KX-TG6532, KX-TG6533, KX-TG6534, KX-TG6541, KX-TG6542, KX-TG6543, KX-TG6544, KX-TG6545 Uniden: D2997 Wireless Handset, D3280, D3288 Wireless Handset, DCT6485, DCT758-2, CLX485, EX13226, EX18560, EXA7250, EXA8955, EXS9966, TCX905, TRU9380, TRU9466, TRU9485, TRU9488, WDect3305, WDect3315, WDect3316, XDECT R055 Gigaset: BT200, BT201 BT101,102 Please do not buy this headset for cell phone, computer or laptop!!!