This is a really cool radius from a big Amphibian from the famous Texas Red Beds. Some of the amphibians from this area, such as Eryops, were enormous, growing up to three meters in length. 
 
This specimen has two repairs, but it's still a very cool fossil for sale, one I haven't personally seen before.
 
Location: Texas Red Beds
 
Age: Approx 280 million years old (Permian)
 
Length: 66 milimeters (two repairs)