SPROCKET HUB 1 SIDE, 7T, 1.85"ID 4.50"OD X 1.00"Wide. Machined internal for bearing. LOW PROFILE QUICK SWITCH CORN HEADER - 1972 & 1973 MODELS; LOW PROFILE QUICK SWITCH CORN HEADER - 1974 MODELS; LOW PROFILE QUICK SWITCH CORN HEADER - 1975 MODELS.