A lock cylinder for a door including an opening, and operable to interact with a latch bolt assembly. The lock cylinder includes a housing that has a cavity, and a plug assembly that has a casing and a plug housed in the casing and rotatable between a locked position and an unlocked position. The plug is operable to interact with the latch bolt assembly, and the casing is disposed within the cavity. The lock cylinder also includes a spin ring member that at least partially encloses the housing, and an adapter that is configured to be installed in the opening of the door and that includes a spin ring interface engaged with the spin ring member. The adapter further includes a shield portion extendable into the opening of the door, and the spin ring interface and the shield portion are formed as a single piece.