Found in the bottom of a bag, any ideas?

[Couv]

pushes in to something and then turns to lock

My guess too....again, something like part of an ink pen.

 

[Jack Hammer]

It looks like a plastic tip for a dart to me. The kind with a hard plastic board and darts that wont damage drywall.

 

[giwnydiver]

It may be something non-dive gear related like a part of an ink pen. The pointed end makes it puzzling though. Is there an air passage all the way through?

No, there is no air passage all the way through.

 

[giwnydiver]

It has a locking channel starting at the collar.

 

[giwnydiver]

Since found, none of my gear has failed at this point, so......

 

[gypsyjim]

I figure that if, after assembling something there are parts left over, and whatever it is you assembled works, the extra parts were unnecessary..throw them away?

 

[giwnydiver]

Assuming its black oxide steel and not plastic it appears that it pushes in to something and then turns to lock with the round part on top being for centering it, the square tab on the side just below that being one of the two locking tabs (guessing there is one on the other side) and the flats below that for putting a tool on it to turn it when it gets stuck. The point would suggest a tip for something like a spear gun or to stab into a lawn as an anchor at the end of a pole or some such thing. If its for stabbing things maybe its a dull practice tip like they have for arrows since I don't see any barbs. Maybe the tip locks into a larger folding barb assembly though.
If its plastic I guess it could still be the same.
I had to judge the size by the oak wood grain on the table.

Right. But then it has the guides down both sides, so with the locking mechanism, what is it locking in place?
.

 

[Oldbear]

OMG...you guys are missing the obvious.

It is a discombobulater for a pneumatic flux capacitor. Not to be confused with a discombobulator for a hydraulic flux capacitor or the later version a discombobulator for a nuclear flux capacity (as seen in popular culture films of the 1980s).

 

[gypsyjim]

Dodad, thingamagig whatever.

The only way to really find out what it is, is to throw it away.
If it turns out that it was important, this will become obvious, along with it's purpose, the second that it is irretrievably gone.

 

[gypsyjim]

These things you can only learn from hands on experience.