Condencers are actually just a capacitor. The smaller ones like an old Ford ignition system uses are generally rated in micro farads of capacitive reactance. They could be used in any low voltage system from 6 to 32 volts as long as there is a pulsating DC current to make them function and the micro farad rating is something close to what Ford entended them to be.
Napa Echlin parts still seem to be relatively reliable. More and more of this stuff is made in countries where they could care less if it works or not. Major companies that market this stuff should care but it is such a small nitch market for them, they just don't worry much about it. If you get one in three that has the correct rating, you have to consider yourself lucky these days.