i made EXPNeck in my 1.9 server and it works fine but i dunno if it will work on 2.3 or 2.6
798 ExpNecklace 19 141 1 0 0 0 0 2507 2000 0 0 0 0 0 0 0 0 0 0 0 60 100000 100
u can change the rate of multipile from dura fld
if u made it dura 2 then it will Multipile the experience x2 also if its dura 10/10 then it will multipile the exp x10
and if its dura 8/10 then it will multipile the exp x8 not 10.
i think u can also make this function on a ring or any item not necks only just set the shape number (141) and set the dura as u like
i hope i explained the idea well