This is a low level rf noise source which allows you to tune your tuner without emitting any rf from your rig. It is one of the slickest things I have seen. Especially for those of you who have a QRP rig this is the ticket. It connects between your rig and the tuner. To operate, just press the power button and tune your tuner while listening on your receiver. When the noise peaks, you are tuned up without causing any QRM on the band. The case is in good condition, and it works 100%. MFJ lists the 212 for $99. I am asking $45 shipped CONUS. Will accept personal check or USPS money order. For more information contact: W1AAF MJANDA@MFX.NET Phone 207-532-2348.