This pair of Ruger manufactured fifth variation checkered walnut grip panels with silver phoenix factory medallion is for the late variation Mark I semi-auto rimfire pistol with the grip frame marked "A-100" and the magazine button flare on the left side of the frame. This pair of grip panels are in very good condition with light wear. (file photo)

Note: Ruger Mark I semi-auto pistols with the following serial numbers have been observed with this part: 12-11122