An agricultural vehicle (10) including a chassis (12), a feeder housing (14) carried by the chassis (12), a header (100) coupled to the feeder housing (14). The header (100) includes a flexible cutter bar (108) and at least one endless belt (200) positioned rearwardly of the flexible cutter bar (108) and configured to travel in a direction of travel (T) for transporting a crop material to the feeder housing (14). The at least one endless belt (200) includes a first belt (210) having a first width (W210) transverse to the direction of travel (T) and a second belt (220) moveably attached to the first belt (210) and having a second width (W220) transverse to the direction of travel (T) and a front edge (222). The second belt (220) includes a plurality of elongated protrusions (226) transverse to the direction of travel (T) and configured for contacting the crop material, and an engaging feature (228) adjacent to the front edge (222) and configured for moving the second belt (220) in accordance with the flexible
