Cap Screw, M4x8 Hex Socket Countersunk Head 

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

Item No	Models
7-30	LittleMachineShop.com 7600 HiTorque Bench Lathe - 9x20 LittleMachineShop.com 7650 HiTorque Bench Lathe - 9x20

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