Do powder specials on armour stack?

For instance, I have Concentration V on my helmet, chestplate and boots, but I cant tell if they all add up together, or whether id get the same effect if I just had one of them that had Concentration. If they don't stack, then I may just put different powder specials on each

 

They dont stack they just charge up faster. So the effect cap is the same but you get there faster

 

ah, interesting, thanks for telling me. Also hey again :)

 

wish they did lmao ^.^