undef

s1a-iw-grd-vv-20170215t161454-20170215t161522-015296-019126-001_filter

s1a-iw-grd-vh-20170215t161454-20170215t161522-015296-019126-002_filter

s1a-iw-grd-vh-20170215t161454-20170215t161522-015296-019126-002_winddir

s1a-iw-grd-vv-20170215t161454-20170215t161522-015296-019126-001_winddir