LOS magnetic field maps co-spatial to the 46 parent IRIS bursts with measured areas between 1 arcsec² and 4 arcsec². Each plot covers a region of 5″ × 5″ centred on the location of the parent IRIS burst from the closest SDO/HMI image in time, de-rotated to the time of IRIS burst profile detection. The red and blue contours outline regions of positive and negative magnetic fields saturated at 20 G and −20 G, respectively, whilst the orange contours outline the approximate locations of the parent IRIS bursts. Opposite polarity magnetic fields are found within the FOV for 43 (93%) of these parent IRIS bursts.