This launcher is 10 1/2 inches long. The bore is 2" diameter and 7 1/2 " deep. The wing nut brass ring rotates to expose holes which vent gas in varying amounts thus setting the projectile range. Attachment is a straight slot with rotating ring to trap the front sight. A long lee barrel fits but cannot lock in place. There are no markings.
Attachment 96802Attachment 96803