undef

s1a-iw-grd-vv-20170611t102523-20170611t102548-016985-01c474-001_filter

s1a-iw-grd-vh-20170611t102523-20170611t102548-016985-01c474-002_filter

s1a-iw-grd-vv-20170611t102523-20170611t102548-016985-01c474-001_winddir

s1a-iw-grd-vh-20170611t102523-20170611t102548-016985-01c474-002_winddir