This Stamp Confused Me Pls ID

in scott their are several types and colors of 2c Washington I II III V Va etc can any body help me identifying this .. also the year 1921 which overprinted it also has single line S water mark

I think that this may be Scott 528. The quality of the printing leads me to believe that this is an offset issue. While a higher resolution scan would be helpful, I think this is likely a type V, issued in 1920. Which would be in agreement with the 1921 cancellation date. Hopefully one of the Washington-Franklin experts will chime in and tell both of us what it really is.
Added: I really need to read postings more carefully. The offset varieties are not watermarked. So you can ignore my guess! Moreover, type V is Scott 527 rather than 528, so even if I had been right about it being offset type V, I would have had the id wrong.

you can be assured this stamp has no watermark

The watermark single S is very clear the third right of the stamp

I see a star and a 5 or S indentation in the back, but I do not believe that is a watermark

This is an off-set printed stamp. All off-set printings were on un-watermarked paper. Did you put the stamp in lighter fluid or watermark detection fluid to determine the watermark or are you used some other method to see a watermark?

ok thanks for all it seem the waves which let me imaging single S

The stamp is a type Va, Scott 528. The two missing dots in the nose can be seen in the image, but a better scan would be appreciated. The color is characteristic of an offset printing.