Clydesdale, the down and bonding conductors come with UL designations of Class 1 and Class 2 conductors. Both are similar in design and do not look anything like you are use to. They do not come in standard sizes like # 6, 1/0, or 500 MCM, rather something like 29x17 woven or 32x17 ropelay. Which means the cable is 29 strands of 17 gauge wire in a woven pattern. It looks like a braided wire like a coax shield, so it has a lot of surface area. It is about the size of 1/0 and 3/0 depending on the Class.