Most significantly, it has been converted from a monaural to a stereo record changer that can now play older mono 45 RPM records (1950s & 60s) as well as the more modern (1970s to 2000s) stereo 45s. It is designed for external amplification and requires being connected to the "Aux" or "Phono" input of an external receiver or phono preamp via RCA plugs (two, since this one has been converted to stereo).
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