MFJ-392B is perfect for amateur radio and shortwave listening. Great for all modes -- SSB, FM, AM, data, and CW. Each earphone has an individual volume control. Superb padded headband and ear cushioned design makes listening extremely comfortable. You'll forget they're even there as you listen to stations all over the world! High-performance driver unit reproduces enhanced communication sound. Signals never sounded so crystal clear! MFJ-392B will bring out speech fidelity you never knew existed. Has free 1/4 inch phono adapter. Near zero loss on signal transmission from the gold plated plug and cord. Super lightweight earphones (8 ounces) come with 9 feet of cord -- lets you easily move about and still listen to your radio. MFJ-392B handles 450 mW and has a frequency response of 100-24,000 Hz. Impedance is 16 Ohms at 1 KHz, sensitivity is 102dB/mW. Works in mono or stereo mode. The MFJ-392B also comes with MFJ's No Matter What Warranty.