Fernandes Sustainer Kit FSK-401-Basic With Single Coil Driver The Fernandes FSK-401-Basic Sustainer Pickup Kit delivers the power of infinite sustain in any guitar with a neck single coil pickup configuration. Taking all the optional components out of the complete FSK-401 (Bridge humbucker, pickup selector switch, volume and tone pots), but with all its key features, including 3 modes (Standard, Harmonic and Mix) and Sustainer Intensity Control (Potentiometer and connectors included).