The gun is a 10g and most 10g guns will usually be on a 3 frame. The lug on this one is marked with both a 2 and a 3. Both are different sizes and also of different fonts and struck with different force. The size and font are correct for the 3 stamp, not the 2 stamp. So, this gun is a 3 frame, not a 2 as the seller represents.
Regarding the guns hook and suspicion that the barrels in photo 8 are different than that in photo 10, this is just likely an illusion caused by the angle of the camera. The same subtle markings are visible on the hook in both photos.
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