Cap Screw, M4x25, Socket Head 

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

Item No	Models
2-26	LittleMachineShop.com 7650 HiTorque Bench Lathe - 9x20
407	LittleMachineShop.com 3595 HiTorque Bench Lathe - 8.5x20 LittleMachineShop.com 7550 HiTorque Bench Lathe - 8.5x20

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