bushmaster A-3 carry handle

are the windage adjustments 1 MOA or 1/2 MOA, i have seen bushmaster publications saying both. all the detachable carry handles i have seen are marked 6/3 where my A2 has 8/3,i was under the impression that these are callibrated with 1 MOA windage adjustments, but the bushmaster website contradicts that. however, the bushmaster printed catalog states the A3 carry handle is in 1 MOA windage. what is right?