firmware for xperia z ultra :
to download xperia z ultra android 5.1.1 click herto download xperia z ultra android 5.0.2 click her
to download xperia z ultra android 4.4.4 click her
after you download the firmware change .rar or .zip to .ftf
flashtool for xperia z ultra :
to download flashtool for windows click her