undef
s1a-iw-grd-vh-20190912t055223-20190912t055248-028984-034991-002_filter
s1a-iw-grd-vv-20190912t055223-20190912t055248-028984-034991-001_filter
s1a-iw-grd-vh-20190912t055223-20190912t055248-028984-034991-002_winddir
s1a-iw-grd-vv-20190912t055223-20190912t055248-028984-034991-001_winddir