Corn Head, Row Unit, Gearbox, Gear, fits John Deere, Cluster Gear Assembly. Models: 443, 444, 444SH, 543, 546, 642, 643, 643SH, 644, 645, 842, 843, 844, 1243, 493, 494, 592, 594, 692, 693, 694, 892, 893, 894, 1092, 1290, 1291, 1293.