We work on old vehicles... and the chances are that if you're reading this then from time to time you do too.
One of the common questions we see on forums from owners of older stuff is "how do I test my [insert electrical component here]". The answer invariably involves the use of a tool called a multimeter.
Now, you can spend hundreds of pounds on a multimeter, but we realise that in all honesty its one of those tools that whilst invaluable when you need it will just sit in your toolbox (or glovebox) for most of the time. So a sensibly priced one makes a lot of sense.
Reads Voltage (AC and DC), Resistance (Ohms), Current (Amps) which are basically all you'll need to diagnose most issues.