I think that is the 'MX-TALON' replaced by the 'MX-PTZ' tweezers:
http://www.okinternational.com/product_soldering/mxPTZ
I suspect a broken wire in the area of the rotating strain relief.
I also suspect your fastest, cheapest route is to send the tool
to OK International for repair. They treated me right
years ago when I had a broken station.
What's the worst thing they could say?
sup...@okintl.com
--Winston