TRIPROC 3 In 1 Monaural 4 Pin RJ9 Telephone Headset For Landline Phones

Specification: Only compatible with RJ9 Port call center corded telephone devices. 3 kinds of wearing mode 100ohms speaker, to ensure the perfect voice quality Microphone type: electret condenser microphone(ECM) Microphone sensitivity: 40db2db Microphone voltage: 2.0v Receiver impedance: 10010 ohm Package Included: 1 x RJ9 Plug Monaural Headset 3 x Headset Hook (ear hook, back-wearing, head-wearing) NOTE: If you can not hear or others can not hear you, please try to adjust the adapter. How to use: 1, Plug the adapter (the headset comes with it) into the phone RJ9 port, then plug the headset into the adapter. 2, There is a line sequence switch on the adapter(it has the numbers 1 - 8). Note: Make sure to try each of the 8 "Channels"**until you find the one where you can hear them and they can hear you. Note: 1,please make sure the device can be compatible for 4pin RJ9 Crystal Head. 2,this headset just can be compatible for professional call center phone, may not be compatible for cordless phone , please make sure the port before order. 3,use the headset with adapter, can be compatible more different call center phones. the adapter have 8 modes, try to test every kinds to your device.4,this headset just can be compatible for cord phone , not for cordless phone.