undef

s1a-iw-grd-vh-20170905t122514-20170905t122539-018240-01eaa3-002_filter

s1a-iw-grd-vv-20170905t122514-20170905t122539-018240-01eaa3-001_filter

s1a-iw-grd-vh-20170905t122514-20170905t122539-018240-01eaa3-002_winddir

s1a-iw-grd-vv-20170905t122514-20170905t122539-018240-01eaa3-001_winddir