I would guess it's a Norstrand dual coil.
I don't think I would actually modify my bass, but I would love to have a Sadowsky with the Nordy DC in bridge position and have it equipped with a three-way switching Series/Par/Single (phantom coil). The bass that I just sold today to fund the Sadowsky is a 2006 Fender American Deluxe Precision 5. It has that Bill Lawrence designed dual coil in the bridge position, and I love it. I also have (and am selling) a Fender Roscoe Beck 5 that has the same PU but with the switching I described. I love it as well.
To add such a feature to a Sadowsky would be very cool, IMO.