A very handy piece of equipment is a multimeter. They come in two basic flavors: digital and analog. Each has its pluses and minuses. The digital meter can give very precise readings of voltage, etc. It is great for checking the state of batteries. When mucking around with an electrical system (e.g. the battery system in Ginny's Lexus) a precise readout of voltage is a good thing.

On the other hand, I am always happy to use an analog model, especially when chasing down intermittent phenomena. The swing of the needle can give you an indication of which way things are going. That can be handy. When checking the resistance of aviation spark plugs, it is hard to get a good contact. The analog meter gets way behind the curve and you can never get a good reading unless you get lucky with good contact. The analog meter shows you the ups and downs and you get a good feeling of what the resistance is.

So what? Well, the leads of my ancient Radio Shack analog multimeter are getting pretty flaky. So I wanted to get some replacements. You can find hundreds of test leads, but they all have banana clips. I need the pin type plugs. I finally found one guy who had them on eBay. BTW, Radio Shack, what's left of it, doesn't stock the needed leads.