I've had this plug for years I now just have time to look through all my plug an really enjoy them.But this one I'm lost on what is the plastic piece on the top of the plug for. an does anyone know the builder?
thank you will check back, GOOD LUCK GOOD PLUGGIN

Just guessin'--Maybe a cover for a port if you wanta weight the plug?

Bunker oil chamber maybe

I have one also. I have often wondered what it was for??

does anyone know the builder?? Good Luck Good Plugin