Key, 4x28 mm 

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

Item No	Models
114	LittleMachineShop.com 4660 HiTorque Micro Mill LittleMachineShop.com 4700 HiTorque Micro Mill
12	LittleMachineShop.com 4100 HiTorque Mini Lathe - 7x12 LittleMachineShop.com 4200 HiTorque Mini Lathe - 7x12 LittleMachineShop.com 5100 HiTorque Mini Lathe - 7x16 LittleMachineshop.com 5200 HiTorque Mini Lathe - 7x16 Various SC2-US SIEG Mini Lathe LittleMachineShop.com 7300 HiTorque Mini Lathe - 7x16 LittleMachineShop.com 7350 HiTorque Mini Lathe - 7x16 Micro-Mark 84631 MicroLux Mini Lathe - 7x16
25	LittleMachineShop.com 7450 HiTorque Mini Lathe - 7x16
79	Harbor Freight 47158 Central Machinery Micro Mill Clarke CMD10 Metalworker Micro Mill Various X1-US SIEG Micro Mill

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