The advantages of a 12-inch arm are well known. The offset angle is less than that of a 9- or 10-inch arm; resulting in a significant (27 percent!) reduction of tracking error. This results in better trackability and lower inner grove distortion. The U-12’s arm tube is made of carbon fiber and outfitted with silver wire. All parts are rounded for better noise rejection. Even with its increased length, the U-12 is a medium-mass arm at 13 grams. The bearings are military spec, of a fixed-gimbal type that results in better arm stability and superior imaging.