undef

s1a-iw-grd-vv-20180605t215234-20180605t215308-022227-0267a3-001_filter

s1a-iw-grd-vh-20180605t215234-20180605t215308-022227-0267a3-002_filter

s1a-iw-grd-vv-20180605t215234-20180605t215308-022227-0267a3-001_winddir

s1a-iw-grd-vh-20180605t215234-20180605t215308-022227-0267a3-002_winddir