thats an xtr 951 it comes as part of the mech ,there spring loaded too and removable to fit another 950 series? the idea of them is to loose the final loop and aid shifting, they work well oh and the cable's too long 
p.s the other types work great on vee brakes too.
heres my m900 with a problem solver
p.s the other types work great on vee brakes too.
heres my m900 with a problem solver
me bad, yeah what stevo said, nice link 
