Eames short H base  

Lounge height H-base.  Not that common, but not that rare either. I have a few of them in both zinc and black.

Thank you woodywood, I had one other question about the fiberglass, I was told that the more fibers means that is an older model. This particular orange chair has very large amount of textures and visible fibers unlike my other chairs...do you think this might be a late 50s model?

The fiberglass might simply be weathered a bit, giving the shell an older look? The Summit circle S embossed logo dates the shell from 1960 or later.
The use of the plastic glides on the base began in 1957 and were used throughout the 60s and 70s.
 

Thank you Eameshead. You may be right about it being weathered. It's odd cause the whole shell has that effect, also the S on the base has no circle, not entirely sure if that means anything.

I just got these two today. They are both obviously weathered but there is not a major difference between the top and bottom of the chair. Very very grainy. They came as a pair from the same house. Both are summits one has the S in a circle the other has a almost unnoticeable small s with no circle.
I would be curious of anyone's idea of a possible production date of these, also I would find it very hard to believe they were collected and assembled at different times. They are equally aged and they did not come from a dealer just a neighborhood garage sale. So what would be the opinion of the different markings on each chair?
Pictures 2,3,4,5 are all of the same chair. Picture 6 is of the other chair.
I hope this might help you Kyle! And also maybe help me! Thanks!

FLagent,
Going by the bases and plastic base glides, these are 1957 or later chairs.
The circled S shell was probably made in 1960 or later.
The shell with only the stamp was probably made a bit earlier.
Though the chairs were most likely offered and sold as a pair, the shell with the stamp (and no circled S) was probably produced a short time before 1960, before they changed the markings.
There is often quite a lot of overlap seen with these pairings / markings / chair and base combinations. Probably due to older stock at the factory being paired up with newer stock as demand and production dictated.
This pair was probably used outside for some time, causing the "grainy" appearance you mentioned. Sometimes the appearance gets more interesting, as the original shine wears away. Not always a bad trade off...  as long as the fiberglass fibers don't  become exposed.
Hope this helps.

Yes, i think that your correct FLagent. Its a little tough to search dates on these things. Most likley there was an overlap of company stock just as you said. I belive the orange chair is from 1960-1970 due to its color. They had quite a few different changes in colors and fibers after the 70s.