The components on PCBs only seem to get smaller and smaller. I frequently need to put the oscilloscope probe on a fine pitch QFPN pin, or on a tiny 402 resistor. My eyes aren’t what they used to be. Its handy to have a lightweight glass lens magnifier, within easy reach, lurking around your desk. I use the 5x Bausch & Lomb Watchmaker Loupe. It retails at $9 from Amazon. Its probably no better than any other loupe, I just happen to have used it.

Not bad, I have a couple of these around the lab and often throw one in my bag when I’m travelling.

They’re no substitute for a decent bench microscope, but the first time you use a loupe you’ll wonder how you ever got by without on.