 The pistol grip panels and magazines from older Standard models can not be used on post-1971 pistols due to this change, but the later magazines can still be used on pre-1971 guns by moving the magazine follower button to the opposite side.As the Standard model reached the end of its product lifecycle in 1981, a special edition run of 5000 4.75-inch pistols built of stainless steel were manufactured.These pistols were shipped in special wooden cases and featured an engraving of Bill Ruger's signature.