[MSNoise] instrument code

in msnoise admin, configuration > station, what is the correct format for the "instrument" field, and where should I take this from. my responses are not being removed and I have tried using obspy inv, resp files, XMLs and pazs. apologies for the rudimentary question. -a -- Ashton F. Flinders, Ph.D U.S. Geological Survey 345 Middlefield Road Menlo Park, CA 94025 (650) 329-5050