Ruger MKII/MKIII 22/45 Bumper Magazine by Majestic Arms-Single

Ruger MKII/MKIII 22/45 Bumper Magazines...
Dump Your Empty Mag, Then "BUMP" One of These for Fast, Secure Reloads!
  The bumper pad looks and functions just like the ones used by speed shooting 1911 competitors. You insert a fresh (loaded) magazine and then "Bump" the base with the palm of your hand to be sure it is fully inserted, locked, and loaded. Never has 22/45 magazine insertion been this definite and reliable... And It Looks Cool, Too!
  But That's Not All! The magazine itself has been re-engineered for universal fit in BOTH Ruger Mk II and Ruger Mk III versions of the 22/45... No more confusion or mix-ups with different versions of 22/45 pistols... Even More Reliability!
  (Please Note: These mags do NOT fit Mk I, II, III, IV, or IV 22/45 pistols... Only Mk II/III 22/45 Versions)