PART ID from photo?

[jjrothWA]

48296


Does anyone recognize this part, as for being either a Ithaca / SKB Model 900, Brwng A-5 lightweight 12ga?

Thanks.

[Sunray]

Any part of it threaded?
Not seeing anything remotely like it on GunParts Schematics or either model. Which aren't enlargeable enough for this geezer to see it well.
Not seeing it on Auto 5 exploded drawings I can see either. Lots of free .pdf's on line.
Or on SKB drawings.
https://www.skbshotguns.com/owner-support/guides-manuals/parts-breakdowns