What you were looking at was the Thompson Center Black Diamond. I am not sure if the XR comes in those kits. If the rifle had a 22 inch barrel it is the standard Black Diamond...
They are a great shooting rifle and the warranty is second to none. With the kit it does get you shooting much faster. Get a little powder and some projectiles and your ready to make smoke.
I have a Black Diamond XR and it is a fine shooting rifle....
You can go to their site and read about the rifles..
T/C Arms