This listing is for a ‘consecutive’ pair of vintage Yamaha NS-10MC Monitor Speakers. While they aren't a traditional single-box matched set, they are considered an ‘interlocking consecutive pair’ as they possess consecutive manufacturing serial numbers (right speaker 104668A and left speaker 104669B). This means that they were built back-to-back on the exact same assembly day in 1987/1988, ensuring identical wood density, component tolerances, and acoustic symmetry. Because there is one "A" (right) unit and one "B" (left) unit, they still function perfectly as a symmetrical left/right horizontal mirror on a mixing console. I am the original owner; I bought them new in the late 90s. They have only been used in my home studio, which is a non-smoking environment. All photos are of the actual item that will ship to you.