Key, 4x40 mm 

In your instruction manual, this part appears on the parts list as:

Item No	Models
4-20	LittleMachineShop.com 7600 HiTorque Bench Lathe - 9x20 LittleMachineShop.com 7650 HiTorque Bench Lathe - 9x20
84	Grizzly G0463 Grizzly Small Mill Harbor Freight 93885 Central Machinery Small Mill Various X3-US SIEG Small Mill Woodstock International M1110 Shop Fox Small Mill

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