The xxM46M-B is an M4 shape soapbar for the neck position. It is 4.00" (101.6 mm) long and 1.50" (38.1 mm( wide. The split-coil design features deep tone.
The pickup is designed for extended string width of 74 to 90mm in low-curvature fingerboards.
This is an "original series" bass pickup with a passive design. It is cast in epoxy to remove unwanted feedback and microphonics.