undef

s1a-iw-grd-vv-20171229t100059-20171229t100124-019916-021e78-001_filter

s1a-iw-grd-vh-20171229t100059-20171229t100124-019916-021e78-002_filter

s1a-iw-grd-vh-20171229t100059-20171229t100124-019916-021e78-002_winddir

s1a-iw-grd-vv-20171229t100059-20171229t100124-019916-021e78-001_winddir