About this detail of the Tiger
The Tiger was designed with tracks significantly wider than the hull. It required side skirts to prevent mud being thrown up by the tracks.
There were no side skirts on the Tiger prototype "V1", nor the first production Tiger (chassis 250001), nor the nine Tigers that were issued to s.Pz.Abt.502 at Leningrad in 1942. Some Tigers were then issued to s.Pz.Abt.501 without side skirts, but they attached skirts to their Tigers while still training in Germany. All subsequent Tigers were factory-fitted with side skirts.
Because the Tiger's hull had the maximum allowed width for rail transport in Europe at the time, the side skirts were made removable. They were broken into 4 segments per side, each held in place by 4 bolts.
This photo of the Tiger in Bovington Museum shows the attachment points for the skirts. 16 mounting blocks with threaded holes were welded to each side of the hull.
In the original design for the skirts, the mounts were placed equidistant from the bottom edge of the sponson armour, allowing the factory workers to position them easily. But because the sponson edge had a slight bend in it, the line of mounting blocks was also bent. It was necessary to put the central break between segments close to the bend; therefore the front two segments of skirting were shorter than the rear two.
This diagram shows the how the spacing of the mounting blocks differed at front and back.
The above diagram shows a profile of a side skirt, bolted onto a mounting block. It was made of two portions of sheet metal. The outer edge had a lip.
This is a view of a museum Tiger with its side skirts installed. As you can see, there are no end caps or stiffeners under them.
These are views of the front and back side skirts, showing the difference in length (not to the same scale).
This is a set of side skirts installed. The bend in the line is obvious.
The first change to the skirt design was to simplify them by making them from a single sheet of metal. This museum photo shows the second type. Some of these simplified side skirts reached Africa on the last few Tigers of s.Pz.Abt. 501.
In December 1942, the side skirts were altered again. All segments were made the same length, and the welded mounts were put in a straight line. This diagram shows the new positions of the welded mounts, and their uniform spacing.
This third type of skirting had 3 stiffening webs underneath each segment, except that the outer ends had full covers rather than webs.
This is the underside of a side skirt from the Tiger at Bovington Museum, before restoration. The original red primer can be seen where the mounting blocks were attached, but I don't know if the rest of the paint is original.
The width of the skirt is 280mm  ; adding the thickness of the sheet metal and the vehicle's nominal hull width, gives exactly the figure of 3705mm overall that is given in [2, see Spielberger page 208] .
As this museum photo shows, there were no end covers on the internal segment boundaries. So now the tank had 3 different kinds of segment (left, right and inner).