Materials & Construction:

MAGNET: Alnico 5 for warm and rich tone.
Coil: 4-wire lead with quick connect terminals, unsealed wax.
Coil Winding: Dual black coils.
DC RESISTANCE: BB1 averages 8k ohms, BB2 averages 9k ohms.
Pickup hole spacing: 50 mm.
Tone characteristics:

BB1: Provides rich, warm tone and balanced coils.
BB2: Similar to BB1 but slightly over-wound to increase output.