(Magwell & Weight Compatible) Install your P320 firing control unit into this Grip Module Assembly to convert to a P320 X-Series Full size, chambered in 9mm, .357 SIG, .40AUTO. Requires the 9mm, .357 SIG and .40AUTO slide and barrel.*Please note- This grip module DOES NOT include the extended magwell and internal weight.- The X-Series Grip Modules will not work with magazines that have “SIG SAUER” on the baseplate. They are compatible with the baseplates that have the SIG Mark on it.