The MM42CBJD3 is the Music Man StingRay bass replacement pickup. The quad-coil design is splittable and offers deep tone, with strong lows.
The Classic Bass Series bass pickups are passive designs featuring an extended and more resonant frequency range. They have far more "air" and definition at the top without sacrificing lows and low mids. They are cast in epoxy to remove unwanted feedback and microphonics.