2 m long freestanding tube equipped with 2 windows.
2,5 m long freestanding tube equipped with 3 windows.
3 m long freestanding tube equipped with 3 windows.
3,5 m long freestanding tube equipped with 4 windows.
4 m long freestanding tube equipped with 4 windows.
4,5 m long freestanding tube equipped with 4 windows.
5 m long freestanding tube equipped with 5 windows.