ftp.ntua.gr:/debian/dists/stretch/main/installer-armhf/20170615/images/u-boot/Firefly-RK3288/?C=N&O=D 
Icon  Name                                                               Last modified      Size  
[DIR] Parent Directory                                                                        -   
[   ] u-boot.img.gz                                                      15-Jun-2017 11:34  191K  
[   ] u-boot-spl.rksd.gz                                                 15-Jun-2017 11:34   17K  
[   ] Firefly-RK3288.sdcard.img.gz                                       15-Jun-2017 11:34  208K
Apache/2.2 Server at debian.noc.ntua.gr Port 80