Limb-side part of the sunspot in AR12681 observed on 22 September 2017 in Hβ and Hα blue wing and CHROMIS WB 4846 Å. PEBs are visible as small bright features all over the penumbra, some with clear flame morphology pointing straight up between filaments. These PEBs are invisible in the continuum WB image. The direction to the nearest limb is approximately upward along the y-axis. The top image includes six squares labeled A–F that mark ROIs that are shown in detail in Fig. 2. An animation of this figure is available online. This animation shows a spectral scan through the Hβ and Hα lines.