Here is a single PB Flip-Flop circuit I have used in the past, minimal electronics, 3 sets of relay contacts available.

 

Wow! Seriously Max?

 

Wow! Seriously Max?

Why? You don't like it!

 

I do and I don't, I think.
Still wrapping my head around it.

 

One advantage is many circuits require external relay(s) , with this, relays are part of the flip flop!

 

OK, MAX now translate it into ladder logic to make it easy to see how it works.

 

I have the original Technical Note entry results on it from the "Journal of the Experimental Analysis of Behaviour" 1969 , Somewhere if I can find it.
A two Relay Flip-Flop.
In the original test, no malfunctions were seen in 2000 operations at 12/sec.
I optimized it for my use with Omron 24vdc relays.

 

If anyone interested, Updated schematic.
Also Original report.