http://imageshack.us/g/692/1000668umzq.jpg/ Link to new pics. I believe it is a 12 gauge. There is a letter T, then a number 3 to the 12th power, a small letter C above that. On the back as seen in the last two photos there is a 5 and a 1. Hopefully the pictures are decent enough to see the markings. Thanks for the help.