About this detail of the Tiger
The Tiger had a wide, flat ring on the lower inside of its turret. The designers used this as a table, by attaching sheet-metal coamings to it.
The first evidence that I have for the use of coamings is in the Bovington vehicle. This tank has the third known arrangement of turret stowage.
This is a view of the front left of the turret. A piece of coaming runs forward from the traverse wheel to the front wall. The turret ring, in the lower foreground, has been painted ivory, but we can see a darker colour beyond it.
Looking down into the corner, we can see that it forms a niche over 100mm wide. The hidden side of the coaming has been painted ivory. The bottom surface is a very dark color, most likely primer red. The red-painted fitting is the oil filling point for the left-hand gun bearing.
This diagram shows how the coaming fits up against the shaft of the traverse wheel. (I haven't seen this curved area in the real tank, so there is some guesswork here.)
A plan view shows how the coaming is bent slightly to fit between the turret parts. The front end of the coaming is held by one of the screws of the mantlet sealing clamps.
[1] Survey of Tiger 250122, at Bovington museum, by David Byrden