Standard parallel guide, square cross section. But none is like the other. Each guide is optimised for the highest output.
Standard parallel guide, rectangular cross section.
Tapered guide, here the highest cross section in the world, starting from 417 mm.
Elliptic or parabolic shape in both directions.
Double guide units. Two channels are connected and share a common vacuum housing.
The splitter section, the start of a dual, triple or quad guide.
Art and science, triple guide units.
Quad Guide, the highest level - up to now
Octagon Guide, challenging to manufacture
Free standing, self evacuated guide. What is not recommended for glass, for metallic substrate it is. No extra vacuum housing is needed.