Outer shell The multifunctional outer shell gives the T-cell its individual appearance and protects it from external effects.

The versatile design of its outer shell means that the T-cell can be integrated into various contexts and respond to a range of different user requirements. As an object in public areas, it is subject to strict safety requirements. The outer shell serves as a protective barrier and makes the T-cell secure against terrorism. Furthermore, it fulfils structural functions to protect against climatic effects and reduces the sound emissions from the T-cell to a barely perceptible minimum. As a thermally effective shell, it ensures that the plant has a regulated surface temperature and minimises both heat losses in outdoor use and heat intakes in indoor use.

Aside from its protective function, the outer shell also allows easy maintenance of the T-cell. If a machine has to be dismantled for maintenance in a service facility, the shell remains independently on location and preserves the appearance of the plant in the public area, even during maintenance.