Two Different SureFire A19 adapters?

I have recently purchased two A19 adapters here on the forum. They not only look different, but they fit different. The A19 on the left does not screw down flush with the body of my 3P. The one on the right does and is slightly taller. The one on the right also has the same style (grooves on either side of knurling) as the original original 6P, which I realize the A19 was designed for. Was there an even earlier version of the 6P(Originalx3) that had different thread lengths and no grooves on sides of knurling, or is the one on the left something else altogether that I am not familiar with?

Thanks,

Jim

Jim-

Could one odd-fitting one possibly be an "A12", meant to convert a Surefire weapons-mounted 3V into a 6V?

Just one possibility...

I don't know enough about SF accessories but that is what I was getting at. The do have a lot of adapters don't they. Maybe Al or somebody else will recognize it. I got the left one first and wondered why it didn't fit flush, but then looking at the tailcap, which has a gap between itself and the body, I figured it was intentional. If I wouldn't have bought the second one, I never would have questioned it...

SureFires evolve... You've proven it right there.
I have a few of what I understood to be an older version (on the left) without the grooves on either side of the knurling.

Al

Thanks Al. I knew i could count on you. Just to follow up, was there a matching 6P without grooves (or 3P) for this "old style" A19 adapter which also allowed it to screw down flush with the body?

Jim

They improved the knurling for sure, alot better than is used to be.

I would love to see one of the later A19's as mine looks more like the one on the left. The threats do fit nicely, the curling could be more agressive. I also have a 9P with these oldstyle curlings w/o grooves. My A14 and A20 do look like the one on the right side though.

Klaus.

Constant SF changes and variations. I even have two 6P bodies of different lengths.

Brightnorm