The modular wall includes a sheet pile wall 12 with support brackets 20 that provide cantilever support to a facade of interlocking rows of blocks 30-34. The primer flare is formed from a fast burning pyrotechnic composition and is adapted to produce an intense infra-red source of short duration on ignition. In a method for operating the tachograph, as a result of high security requirements, the data transfer between the data memory and the tachograph is extremely time-intensive. The bottom surface functions as a retro-reflector when the optical switch is assembled. In the terminal forming step, the terminal is formed by applying an ultrasonic wave to a high-melting-point solder while the high-melting-point solder is heated to melt.