Brand new 686-plus.
Initially installing the part revealed significant side to side wobble. Inspection showed the small block on the back of the release that interfaces with the gun is too tall.
Filing this block down is necessary for proper fit and function.
Can’t say exactly how much I had to file off, but far enough that the little plus sign on the part is gone, and I had to keep going a little past that.
Now it’s perfect, it sits flat on the gun’s side plate with a gap that I can barely slide a piece of paper into. No wobble and 100% functionality.
In closing, it’s a beautifully machined part, but may not be “plug and play”. YMMV.