They look very useful.<br><br>Backup glasses are essential. I keep them in BOB. I never thought of getting a set for the PSK!<br><br>I needed to read instructions on an OTC antihistamine for my son over the weekend at a camping trip. I was amazed to discover that I needed not only my reading glasses, but also a 4x magnifier to read the instructions on the label. It was the smallest print I've seen.<br><br>John