Schatten Design RB-2 Rock-A-Billy Bass Pickup Passive, complete system with bridge pickup, slap pickup and volume control for both pickups, bridge pickup with a thickness of 6.35mm, requires a bridge slot of 5.7mm, will be slightly compressed when installed in the bridge slot, comes with 6.3mm jack socket, that needs to be hooked between the D- and A-string above the tailpiece, slap pickup, that needs to be mounted under the fingerboard with 3M VHB mounting tape, volume control with two thumbwheels for the pickups, that needs to be mounted under the fingerboard with 3M VHB mounting tape, can be connected directly to the bass amp, the sound can be further improved with an external preamp (not included).