undef

s1a-iw-grd-vv-20180107t021126-20180107t021151-020042-022264-001_filter

s1a-iw-grd-vh-20180107t021126-20180107t021151-020042-022264-002_filter

s1a-iw-grd-vv-20180107t021126-20180107t021151-020042-022264-001_winddir

s1a-iw-grd-vh-20180107t021126-20180107t021151-020042-022264-002_winddir