undef

s1a-iw-grd-vv-20170726t100058-20170726t100123-017641-01d877-001_filter

s1a-iw-grd-vh-20170726t100058-20170726t100123-017641-01d877-002_filter

s1a-iw-grd-vh-20170726t100058-20170726t100123-017641-01d877-002_winddir

s1a-iw-grd-vv-20170726t100058-20170726t100123-017641-01d877-001_winddir