Mike, this is a quote from Bruce Spizer's book "The Beatles' Story On Capitol Records: Part Two": "By 1967, consumers in the United States were purchasing stereo equipment and were willing to pay extra for stereo records. At the time Sgt. Pepper was released, Capitol was in the process of phasing out mono records. Thus, mono U.S. pressings of Sgt. pepper are much less common than the stereo version." As many mono enthusiasts would feel, you were one of the few lucky ones who heard Sgt. Pepper for the first time in mono or, as many feel, "the way it should be heard."