Help Identifying Great Britain Stamp

I am a complete novice. This stamp has a large crown watermark. I couldn't tell if it had perforations at one time or not? When looking at the lower left corner there isn't a sign of perforation. Can someone help identify what scott # this would be? I greatly appreciate the help.

It is quite simple: look at the left: you can see the adjoining stamp. So, this, almost certainly, is an imperforate. At top, the width also suggests it was imperforate. So, it raises the question if it indeed has the large crown watermark,


The corner letters must not make it too difficult to find the plate number.

It's an imperforate penny red from the issue of 1841-54. Scott Catalog #3, Stanley Gibbons Catalog #8.
In 1841, they changed the color of the Penny Black to Red to make it easier to see the cancellation and prevent reuse.
The first 40 plates usually come with Maltese Crosses. In 1844, they shifted to numeral cancellations. You can only see the last digit, so we can't tell what town cancelled this stamp.
It can be plated, but not by me.
Yours is barely 4 margins and looks like it has a tear (or crease) at the upper left and maybe another crease 2/3 of the way down on the right.
Minimal value, but a nice example of the design that was used for the first postage stamp.
Enjoy it.

Thank you so much for the assistance.