Requires the 9mm, .357 SIG and .40AUTO slide and barrel This grip module DOES NOT include the extended magwell and internal weight 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. 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.