These are 2.5 ounce tannery run goat leather hides. The size of the pieces are approximately 2 to 9 square feet. They may have imperfections.
Here are the measurements of three random pieces:
19" long by 8" wide (down the middle)
40" long by 25" wide (down the middle)
26" long by 20" wide (down the middle)
The goatskins are a by-product of the food industry. They are not endangered.