Benwah's Recurve...Upgradeable?

I am thinking of obtaining Benwah's Recurve Bow, a "Green" weapon. It has the following stats on it:

-15% damage
-Armor -10 when attacking
-Armor Penetration +20 %
-Marksmanship +1 (20% chance)

Question...Could I add a bow string or bow grip upgrade to this bow, or would one of the built in attributes be overwritten? Was thinking of adding a Barbed bow string to enhance bleeding damage duration on some of my Ranger skills, but dont want to erase and replace any of the above stats that the bow comes with. I guess I am curious if "green" and Named weapons are upgradeable? Thanks!

No
Greens Cannot Be Upgraded.

All unique items, whether perfect or not, cannot be changed in any way. They cannot be modded, dyed, salvaged, or renamed. They can be customised though.

Moreover, the 20% armour penetration (20% chance on hit) part is a Sundering String, so even if this bow could be upgraded, you would lose the armour penetration if you added a Barbed string.

Gwt a 15^50 recurve from collector, and add the mods you want, its sometimes easier that way.