undef

s1a-iw-grd-vh-20150516t215217-20150516t215251-005952-007ab4-002_filter

s1a-iw-grd-vv-20150516t215217-20150516t215251-005952-007ab4-001_filter

s1a-iw-grd-vv-20150516t215217-20150516t215251-005952-007ab4-001_winddir