As i see, you can upgrade it with 3750 golden threads. 

You got chance to get different lvls of it:

Ultimate        -    31.9%

Ultimate+1    -    24.5%

Ultimate+2    -    19.6%

Ultimate+3    -    14.7%

Ultimate+4    -     7.4%

Ultimate+5    -     2%

each lvl give you some more stats, like for armor pattern you can have from 13% to 18%

After you make upgrade - you can repeat it, if you don't like the result. it will cost 3750 golden threads more. So you can do it many times, until you will like your result.