I've had this for years, but I don't know exactly what model it is. I'm hoping the experts here can help me out. My best guess right now is that it was a J-50 but I can't be sure. If it ever had a label in the sound-hole it is long gone. It was in a useless state when I got it - the top was cracked and separated from the sides on the lower bout. It looked like it could be flipped open like the lid of a toy box. Everything is very stable now and it sounds great, i just wish I knew what it was. I've been trying to narrowing it down based on some of the features (unfinished headstock and head/neck volute) and the parts (bridge, tuners, pickguard) but those may have been swapped out at some point. There are extra tuner mounting holes and these tuners have a little black paint on them. I haven't seen this particular bridge on any Gibson. The serial # is 639739 which seems like it dates it as a 1970-1972 from what I can tell. Any info is appreciated!