The SIG SAUER P320 AXG Carry Medium Grip Modules 8900063 are plain.
The Sig P320 Compact magazines will not work with the SIG SAUER P320 AXG Carry Medium Grip Modules 8900063.
Yes, both sig and LOK Grips make panels and back straps for the AXG.
The X-TEN FCU is not compatible with this AXG module. The X-TEN FCU is too large/wide for this module and would not be compatible.
This SIG SAUER P320 AXG Carry Medium Grip Module is not compatible with an M18. The M18 uses a manual safety, this module was designed for P320 model pistols that do not have a manual safety. You can remove the manual safety on your FCU and use this module, but with the manual safety, you cannot use this module.
Sig Sauer states: Precision machined with deep undercuts and an extended beavertail for an ergonomic, comfortable fit, the AXG grip module is fitted with interchangeable Black G10 grip panels from Hogue and a Medium Black back strap.
Sig Sauer does not specify the exact model G10 grips used with this module. I would recommend contacting them directly for more information.
The SIG SAUER P320 AXG Carry Medium Grip Module will work with the 21 round magazines.
The SIG SAUER P320 AXG Carry Medium Grip Modules will work with the 3.6" Pro Cut Slide.
You would need to use a compensator with your slide to fill the gap that will be present when using this SIG SAUER P320 AXG Grip Module.
This SIG SAUER P320 AXG Carry Medium Grip will not fit the P320 Compact .45ACP. We do not have a SIG SAUER P320 AXG Carry Medium Grip for that model P320.