In addition to viewing the sun's luminous outer atmosphere (corona), which under normal circumstances is lost in the glare of the rays, they will be using the eclipse to calculate the star's current diameter, which changes as the sun expends energy.
It has a detachable inner pocket, which is partitioned to enable storage of other items in addition to the camera and lenses, such as a smartphone, while the outer pocket is large enough to accommodate a tablet PC or A4-size file folders.