The ET Supreme Slim Bolo is very similar to the pole rods of the same family. The Slim Bolo is made from IM7 carbon. This quality material makes the rod extremely fast and light. But why does a bolognese rod need to be fast? River species usually take the bait from the same direction as the river is flowing. For this reason, the bites are quick. Anglers have to react to these bites as fast as they can. Even a few seconds can result in losing the fish.