This is a brand new OEM Sig Sauer SP2022 .357 SIG Barrel. This can either be used to replace a worn .357 SIG Barrel or swap out your .40 S&W Barrel for a caliber conversion. When converting from .40 S&W to .357 SIG only the barrel is needed to complete the conversion (magazines are identical). This will NOT work on a SP2022 9mm pistol.
Note: it is not uncommon that new barrels may require fitting. If this is needed on your pistol we suggest using a competent gunsmith.