Small block electronic distributor with rare tan cap with brass posts $40

Ty,
What make? What type of pickup is that, magnetic? How is the gap set in it? How old is it? Did it work well? What was it in? What is it a replacement for? Automatic or stick? Two or four barrel? Did you have any trouble with it? Does it work with a stock Mopar coil and ballast resistor? Does the vacuum advance hold a vacuum?
Thanks, Richard