OPGunner from United States, CA Public Profile

The stock P365 has a small grip for someone with large hands, and the XL grip seemed to be the answer to that situation.
The price at OP was too good to pass up.
What I didn't expect was that the grip is not a drop in replacement for the California version of the P365.
The CA version has a manual safety, and that was not the problem, I knew enough to look for that and this grip has the safety relief.
The CA version also has a loaded chamber indicator and that may be the issue, or possibly an empty chamber lockout, honestly I don't remember at the moment, but whatever the case, the grip module would need to have some material removed from an area inside the grip, and adjacent to the trigger hole, in order for the Fire Control Unit to seat properly.
It seems that all the Sig Sauer grip modules are like this, I looked at all modules at my local gun shop and they were all the same story.
About a 1CM square of polymer material would have to be cut out or filed away in order for the grip module to work with the CA guns.
Maybe this is common knowledge, but I wasn't aware of that at the time.

When I ordered this I should have paid closer attention to the sidewall thickness around the threads, it was bigger and heavier than I expected.
However, it all worked out, it went on a rifle that could use a little counterweight up front.
It arrived in a nice polymer screw case and included a nut and a crush washer.
The nut didn't work for my barrel because the barrel didn't have enough relief for the nut to seat properly, but the crush washer was all that was needed for the installation.
The brake works well, keeps the muzzle right on target, and looks good too, very heavy duty, it has a flat black grayish finish.