Additionally, this prevents users from purchasing ill-fitting barrels after the fact. While most purchasers will probably choose to use the threaded barrel, if an unthreaded barrel is needed for any reason, the XDM OSP can be quickly swapped. These features allow users to choose an optic and silencer to fit their needs. It also comes with a factory milled slide and suppressor-height iron sights. The Springfield XDM Optical Sight Pistol (OSP) now comes with two barrels-one threaded barrel with a protector along with a standard flush barrel.