The ExpoDisc (4x5.65") lens mount_Praktica Electronic Two camera platforms and one

Two camera platforms and one stopper block are included (both sides have an end stop

with a 28mm-ish field of view and just a happy bit of distortion

The Linhof leveling head is essentially a very low-profile ball head with a 15-degree range of motion

The Fotopro X-4i is a compact tripod with a slightly unusual design: the centre column is “permanently” extended

with some cosmetic wear from normal use and handling

The ExpoDisc (4x5.65") lens mount_Praktica Electronic Two camera platforms and oneThis particular Expodisc is not a disc it's a big 4x5. 65" slab designed to slip into matteboxes but it works the same as the classic. Basically, it's a specialized flat diffuser designed to facilitate setting custom white balance. Rather than hauling around a gray card, or trying to find a plain white surface, or hoping that your camera guesses correctly, you can toss this in front of your lens and lock in an accurate custom white balance in seconds.