Back up a little. Tell me what you are trying to do. What size gun and make, connected to what feeder. All the tweco guns can be ordered direct connect for Lincoln and miller.
And don't need to order an adapter, unless you are changing on from Lincoln to Miller or one of the others. Finding Lincoln adapter for Lincoln guns can be challenging. They seam to put them in different places in the catalog.
If you are trying to adapt to the LF-72 , The parts book has 6 different gun bushings for the drives. Fits tweco/Lincoln guns to OXO to Miller to fast mate to #5 tweco/ lincoln guns. Look in the OPTIONAL EQUIPMENT LISTINGS.

 

If you only want the connector, and not the Tweco # 5 gun bushing, this is what you want. The LF-72 basic feeder (without gun) comes with a #2/4 Tweco bushing.

http://www.bakersgas.com/LINK466-10.html

If you need that Tweco #5 bushing, then you will have to order this...

http://www.bakersgas.com/LINK1500-3.html

 

Yes the LF-72 came with the Tweco 2/4 bushing. I have a Tweco to Lincoln cable adapter that came on my LN-25, but I could not read any numbers on it. And didn't see anything on Lincoln's site that resembled it. I have already ordered the bushing for the K-126 fluxcore gun. Just wanted another cable adapter for the LF-72, I hate robbing parts off one machine to make another one work.
Thanks for the link!