Replacement top gearbox nut fits 42 different Bush Hog models, used to secure output gear to output shaft. Please see fitment list below. If you are not sure this is the correct nut for your application please contact us and we will help you make sure it is correct. 104 Rotary Cutter (Discontinued) - Gearbox & Related Parts For 104 (All Models) 104 Rotary Cutter (Discontinued) - Gearbox Assembly (Obsolete) 104 Rotary Cutter (Discontinued) - Gearbox & Related Parts For 104 (All Models) 104 Rotary Cutter (Discontinued) - Gearbox Assembly (Obsolete) 1050HR Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050HR Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050HR Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050HR Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050HR Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050HR Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050HS Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050HS Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050HS Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050HS Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050HS Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050HS Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050R Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050R Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050R Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050R Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050R Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050R Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050S Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050S Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050S Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1050S Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1050S Rotary Cutter - Gearbox Assembly No. 3 (Obsolete) 1050S Rotary Cutter - Gearbox Assembly No. 4 (Obsolete) 1051R Rotary Cutter - Gearbox Assembly No. 2 (Obsolete) 1051