PC on Gold Fellblade 13<50

Quick PC on a:

Gold 15-22 Vampiric (3:-1) Fellblade of Defence
+13% while health is below 50% hp
+ 5 Armor

Any ideas?
Thanks!

The vampiric hilt is worth more, IMO.
The max for <50% is 20% so thats actually pretty far off.

Thanks for that, I didn't realise that <50% went as high as 20%.