Cap Screw, M4x20, Socket Head 

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

Item No	Models
16	LittleMachineShop.com 3536 HiTorque Bench Lathe - 8.5x16 LittleMachineShop.com 3540 HiTorque Bench Lathe - 8.5x20 LittleMachineShop.com 3595 HiTorque Bench Lathe - 8.5x20 Various SC4-US SIEG Bench Lathe Travers Tools OT218410 OTMT Bench Lathe - 8.5x16 LittleMachineShop.com 7550 HiTorque Bench Lathe - 8.5x20 LittleMachineShop.com 7500 HiTorque Bench Lathe - 8.5x20
204	LittleMachineShop.com 4190 HiTorque Mini Mill
29	LittleMachineShop.com 4660 HiTorque Micro Mill LittleMachineShop.com 4700 HiTorque Micro Mill
71	Harbor Freight 47158 Central Machinery Micro Mill Clarke CMD10 Metalworker Micro Mill Various X1-US SIEG Micro Mill
F14	LittleMachineShop.com 5550 HiTorque Bench Mill Various SX2.7L-US SIEG Bench Mill LittleMachineShop.com 6550 HiTorque Bench Mill

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