Posted By ed custer on 05/24/2014 10:48 PM excelcycle has a Campy 39T chainring for $75.24. I don't think you can use a 11 speed 39T chainring with a ten speed Campy crank as one bolt hole is off set and won't match the Campy ten crank. Otherwise you can use a 11 speed crank/rings with a Campy ten and it will work fine. I've been using one for several years.