[mockingbird812]

310s came in many configurations (I believe all were double points and would work on both BBC & SBCs), electronic, single capacitor, rev/pol single capacitor & rev/pol double capacitor and I am sure there were others. I think they were all non-Vac (mechanical)advance units. And as Professor Mallory said, make sure you couple these dizzys with the right coil/electonic CD unit, rev/pol switch, resistor, etc.