The optical and mechanical design of a 10m-normal incidence monochromator f
or highest resolving power in the energy range from 10 to 40eV will be pres
ented. In order to overcome problems associated with higher order contamina
tion, this beamline will be installed at the quasi-periodic undulator U125-
2 at BESSY II. (C) 2001 Elsevier Science B.V. All rights reserved.