A header (102) has an elongate laterally extending frame (104) and two forwardly extending crop dividers (116, 118) at each end. A gear box (120, 122) is mounted on the front of each crop divider (116, 118). The gearbox (120, 122) has two output shafts (148, 152), a first shaft (148) that is coupled to and drives an elongate reciprocating knife (112) extending across the leading edge of the draper header (102) and a second shaft (152) that is coupled to and drives a crop divider knife (128, 129). The crop divider knife (128, 129) includes a quick coupling (144) that engages a quick coupling (154) mounted on the second shaft (152).