"Marc" wrote in message
...
I'm looking to pick up a clamp-on ammeter/multitester on ebay. Are
these ammeters AC or DC specific or do they read both as a matter of
course.

As Larry says, they are specific.
If you are mostly interested in measuring DC currents on the boat I would
recommend one of the Hall effect units.
I bought a Fluke version on eBay for less, I think, than $100. Very
accurate and sensitive. Get a decent multimeter while you are at it. The
Wavetek handheld units can be obtained at good ebay prices, Fluke somewhat
more.