This is probably one of the most popular HF Power & SWR Meters Heathkit ever made. You'll pretty much always find these at every hamfest. Today, they sell for as much as $75, and I've bought some for as little as $10. They're very easy to repair and calibrate, and work nicely on the ham bands from 160 through 10m. I've found them to be fairly accurate (certainly usable) on 6m. Good up to 2000 watts, and can measure SWR with less than 10 watts excitation. I currently have several of these. This is one I bought back around 1991, and use it with my Heathkit HW-101 transceiver.