anyone ever use one of these?

[CrazyPete]

just picked this up today at a garage sale for get this $25 bucks what are these things worth? its a alt and battery tester no manual tho

 

[Abodybomber]

You scored,Al Bundy . (lol). If that voltmeter works,way good. Automotive electricians,usually love those big readable "sweep meters". Minimum risk,possible maximum win.

 

[67Dart273]

I have the top part (MT540) separate. You can perform on-car tests with it. That thing cost someone a heck of a lot of money, once