The FIELDS instrument combines magnetic and electric field measurements into a single, coordinated experiment. Magnetic fields are measured using both fluxgate and search-coil induction magnetometers mounted on a deployable boom in the spacecraft umbra. FIELDS will make electric field measurements both as a current-biased, resistively-coupled, double-probe instrument (Harvey et al. 1995, Bonnell et al. 2009, Wygant et al. 2013) and as a capacitively-coupled radio and plasma wave instrument (Bougeret et al. 1995, 2008). The V1, V2, V3, and V4 electric field probes are mounted at the base of the Parker Solar Probe, PSP, Thermal Protection System, TPS, or heat shield and deploy out into full sunlight. At the PSP perihelion altitude of 9.8 solar radii, these antennas will reach temperatures of more than 1300°C. Another simple voltage sensor, the V5 antenna, is mounted on the magnetometer boom in the umbra of the spacecraft.