Extendable draper belt

An agricultural vehicle, comprising:

• a chassis;
• a feeder housing carried by the chassis;
• a header coupled to the feeder housing, said header including:
• a flexible cutter bar;
• and
• at least one endless belt positioned rearwardly of the flexible cutter bar and configured to travel in a direction of travel for transporting a crop material to the feeder housing, said at least one endless belt including:
• a first belt having a first width transverse to said direction of travel;
• and
• a second belt moveably attached to the first belt and having a second width transverse to said direction of travel and a front edge, said second belt including:
• a plurality of elongated protrusions transverse to said direction of travel and configured for contacting the crop material;
• and
• an engaging feature adjacent to the front edge and configured for moving the second belt in accordance with said flexible cutter bar,
• wherein said second belt is slideable in a transverse direction to said direction of travel such that said second belt slides forwardly or rearwardly relative to said first belt and in accordance with a movement of said flexible cutter bar.