This part will allow you to mount a TM spec buffer tube on an airsoft Thompson SMG. It mounts with the original mounting hardware of the stock. It has a hole for routing wires through the buffer tube so that the battery can still be stored in the stock.

You will need a small nut that threads onto the buffer tube screw in order to mount the buffer tube to the adapter. You might have to file a few mm off of the screw in order to get the buffer tube to fit tightly onto the adapter. Those few mm shouldn't make a difference if you later want to mount that buffer tube onto an M4.

Due to the policies of CGTrader, I am unable to show the adapter installed. It does work, and it works well.