Overview of the quiet-Sun region observed on 6 June 2019. (a) Interface Region Imaging Spectrograph SJI at the Mg II k 2796 Å. (b) Solar Dynamics Observatory/Helioseismic and Magnetic Imager LOS magnetogram. The white boxes in panels a and b mark the spatial location of the FOV observed with the CHROMIS instrument. (c) Continuum image at 4000 Å. (d) Line-of-sight magnetic field inferred using Milne-Eddington inversions of the Fe I 6173 Å line observed with the CRISP instrument. Panels e and f show images at wavelength offsets of −108.2 and +22.6 mÅ from the Ca II K line core, respectively. Panels g and h display images at wavelength offsets of −15.8 and +64.2 mÅ from the Ca II 8542 Å line core, respectively. A gamma correction with γ = 1.5 and γ = 0.5 was applied on panels a and e–h, respectively. The ROI s (A–H) highlighted by colored squares of 50 × 50 pixels (185) indicate the locations of the Ca II K grains that are analyzed in this paper. Region of interest A shows a CBG in Ca II K narrowband images (panels e and f), the brightenings in other ROI s occurred at different times.