Wolf Creek Dogless #2 ?

Got 1/2 dozen for Christmas to mess with. What is the purpose of the screw and nut welded to the bottom of the pan. I dressed up the pan catch the engages the jaw and got them tripping at around 3.5 lbs. Ran them though the dish washer and just got done waxing them going to set a couple tomorrow.
J

That is used to adjust pan tension. Tighten it down for less tension. I don't use them and cut them off.

I cut mine off too. Mine are 3.5ish too.