What is this nib on my Esterbrook?

[blazingthrough]

So I recently acquired a few Esterbrooks to restore, and received one with a different nib. All it shows is a logo with the letters "SP" and a circle around them, and "MADE IN U.S.A." under and nothing else. Anyone know?

The nib unit fits perfectly into the section. I've attached a picture.

17833

[Brian Anderson]

I can tell you it is definitely NOT an Esterbrook nib. I have seen them before, but do not recall the maker. All Esterbrook renew-points have the Esterbrook name on them.

[blazingthrough]

I can tell you it is definitely NOT an Esterbrook nib. I have seen them before, but do not recall the maker. All Esterbrook renew-points have the Esterbrook name on them.

Interesting. I tried writing with it and it seems like the feed is plugged with ink. Will try cleaning it more and see what happens. Thanks!

[Jon Szanto]

Have you tried unscrewing the nib unit and taking a look? I'm wondering if someone didn't jam a different nib in an Esterbrook collar/feed.