One PSA submission, 3 different types of slab

[Luke]

Note: My submission only included T206s and T207s

Just got back a PSA submission, and noticed there are 3 different kinds of slabs:

1. New, thicker slab with frosted plastic and no seam along the side
2. New, thicker slab with plastic baggie and no seam along the side
3. Slim slab (like the old ones) with baggie and seam along the side

I'm just wondering if this is by design, and if so, what is the reason. #1 seems most common. #2 seems to come with oversized cards. There doesn't seem to be any distinguishing characteristics of the cards that came back in slab #3.

I really like the slim slab with baggie, (#3) and if I could, I would request to have all cards holdered in that slab. Although, with the seam along the side, slab #3 is not as secure as the other two new designs.

Anyway, I just thought it was interesting (my apologies if it is not) and wondered if anyone on here knows anything about it.

In this scan:
Powell and Jordan are in slab #1
Kleinow is in slab #2
Murphy is in slab #3