wkpoor,
Thanks for bringing the URL regarding the Buyers Heavy-Duty 2 5/16in. Cast Steel Coupler 5-Position Mounting Channel from Northern Tool to my attention. I do not mean to offend you with my following comments but from what I can see it is a very Heavy Duty Cast Steel Coupler of the same basic design and internal shortcomings of the common coupler. I'm glad that it works for you but I personally feel that a Forged 2-5/16" Bulldog Collar-Lok Ball Coupler is more foolproof and stronger for my needs. Once the Ball is locked in place by the Collar it is captive and the ball shank would break before the Coupler would open. I have to admit that I've seen some similar designed couplers to the Bulldog and there have been some problems with them.
I noticed that it was bolted in the channel using what looked like SAE Grade 5 Bolts which are probably stronger than the Coupler itself but for my piece of mind I'd be using SAE Grade 8 Bolts. I noticed that it is also available without the channel.
As an old fart I would not trust a coupling that automatically closed by itself and I personally check couplings that someone else attached.
Again, thanks for bringing your type of coupler to my attention,
Jim