The Retell 216 headphone headset is designed so you can listen to Retell recorded calls in privacy. The Retell 216 headphones are compatible with Retell cassette recorders, with MP3 recorders, and pocket recorders.
Also included with the Retell 216 headphones is a mono stereo adapter that is included so that it can be used with mono recorders, and stereo soundcards on a PC.
The Retell 216 headphones do not have a microphone to talk into so can not be used a telephone headset.