S
WOptical spectrometer
WCosmic Origins SpectrographA
WESPRESSO
WFaint Object SpectrographB
WFibre multi-object spectrograph
WFine Guidance Sensor and Near Infrared Imager and Slitless SpectrographC
WGoddard High Resolution Spectrograph
WHigh Accuracy Radial Velocity Planet SearcherD
WInterface Region Imaging Spectrograph
WMIRI (Mid-Infrared Instrument)E
WNIRSpec
WSwiss 1.2-metre Leonhard Euler TelescopeF
WUVS (Juno)
WVisible Multi Object Spectrograph