【NOT for Cell phones and Computers】Direct connect landline telephone headsets ONLY Compatible with Some Specific Phone Models from Polycom Mitel ShoreTel Plantronics Zultys Toshiba NEC Aspire ...

flexible microphone boom arm with 270 degree ... Plx QD "Works with Ciso SPA Series and other Cordless phones with 2,5mm Standard Headset Port.(3 poles with 2 black bands), No Smart phone use.