Elgin/musselman hub grease fitting?

[BFGforme]

Looking for this piece….not sure what it needs but there’s a hole in the rear hub that makes me not want to ride it with that hub because I don’t want to f it up anyone have or know what it needs? Thanks in advance! Here’s pictures of the hole! Who would sell bike without this….can’t be good….

Thanks for any help…

 

[Glenn Rhein]

Looking for this piece….not sure what it needs but there’s a hole in the rear hub that makes me not want to ride it with that hub because I don’t want to f it up anyone have or know what it needs? Thanks in advance! Here’s pictures of the hole! Who would sell bike without this….can’t be good….View attachment 1540193
View attachment 1540194

Thanks for any help…

Grease fittings