Brass Adapter is a useful part typically used for a variety of applications. Use when converting oil lamp to electric. Screw adapter into #2 lamp collar. This reduces collar opening to 1/8 IP. Lamp socket is then easily screwed onto nipple. Brass adapter is also used on lamp socket clusters. In these applications the lamp shade extension screws into it.
This was a hard-to-find part, so glad I found Paxton Hardware, part works perfectly.
Fit my gas lamp perfectly