Model 234/302 from McPherson Inc. is a multipurpose vacuum-UV monochromator that can be fixed to an experiment or to the slit of a larger instrument for use as a predisperser or narrowband variable filter. An aberration-corrected grating produces an in-focus and flat focal plane. It can be used with microchannel plate or CCD detectors. The clean, contaminant-free finish enables rapid pump-down. The device is available as a double monochromator, in that units can be combined and operated with independent scanning drives. It is available with gratings of various groove densities, allowing factory or user configuration for wide wavelength survey or high-resolution zoom spectroscopy.