The Tiger has four grilles on its rear deck; two fixed air inlets and two smaller hinged outlets. In WW2, every Tiger was provided with four mesh screens to attach on these grilles, to keep small debris out of the spaces below.
The screens had a square pattern mesh, and a solid frame formed their edges. The frame was shaped at the sides, as this model shows. Wires were typically used to attach them to the tank.
The Tank Museum should have the original screens from Tiger 131 (they were in the parts bin at the time of its restoration) but apparently they are not considered appropriate. This is a sensible decision, because photographs prove that the real ones easily got damaged.
Instead, Tiger 131 now has a new mesh screens that are different in almost every respect. They have a diamond pattern rather than square; they have no edge frame; they are spot-welded to the deck; and, when last we looked, there was no mesh for the outlet grilles, only the inlets. The fast-rotating fan blades are perhaps in danger from objects falling into their compartment?