Ruger .22 pistol magazine?

[smle-man]

I have a standard model (Mk1) and a Mk2 target .22 pistol. Both take the same magazine with the follower button on the left side of the magazine. I have a magazine that appears to be a Ruger .22 auto pistol magazine but has the button on the right side of the magazine body. What model of Ruger pistol does this fit?

[smle-man]

Never mind....I noticed how easy it is to swap the button from right to left, did so and it fits just fine in both the Mk1 and Mk2. End of issue.