Merino and Poll Merino (no horns) are judged separately in this premier competition, with the Grand Champion Rams and Grand Champion Ewes brought together to determine the Supreme Exhibit on 4 April. Judges look at visual characteristics, fleece type and weight, even scanning each entry with an ultrasound to determine fat depth and muscle. Prior to the competition exhibitors can send in a sample of fleece for Mid Side Sampling, helping to decide which animal is producing the best quality fleeces and therefore should be entered.