A body lighting Swap
The first set of 7 inch rounds I purchased had the added sockets in the bottom like shown above. That was the most pitifull excuse for a bulb socket I have ever seen. The socket for the H4 bulb wasn't much better. I cut that set up with a hacksaw and used the parts to mod my original park lamp fixtures. Then I bought a second set of better made 7 inch rounds for headlights.
After 3 years I can't recall either brand name or vendor.
Bottom line, you get what you pay for, and/or sometimes you dont. Good luck