HOWARD Compatible Tiller Knife Screw with nut Thread: 1/2" UNF L (mm): 38 G (mm): 23 : 12.9 Dimensions (mm): 1/2" UNF x 38, 10.9 Right Knife Code: 180HOW-34R Original Right Knife Code: 5979 Left Knife Code: 180HOW-34L Original Left Knife Code: 5978 Screw & Nut Code: 18030-3903 NS