Will this be compatible with the FCU from the sig P320 M-17?
Referenced product: GRIP-X5-F-943-M-BLK
The grip will need to be modified for the thumb safety on the M17 variants with safety. If the notch is cut into the grip module for the safety lever, it should work. Note that Sig will likely consider the modified grip module to be unsupported (not warrantied) and you would want to retain the original grip module in the event that you would need warranty service on the firearm (return the firearm to factory configuration before sending back to Sig).