I have a CC306 i think , the numbers on the end are 290 HR-12 and 18880 etched in,any ideas , the measured dimensions of the lobes are 1.175 and 1.520 the other lobe measures 1.085 and 1.440 . The dimensions differ by about .004 , I measured all of them and these numbers are the high side numbers(i measured on the good part of the lobes in other words) Thanks for any help!!!