Lead Screw, Bench Lathe 8.5x16  

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

Item No	Models
40	LittleMachineShop.com 3536 HiTorque Bench Lathe - 8.5x16 Various SC4-US SIEG Bench Lathe Travers Tools OT218410 OTMT Bench Lathe - 8.5x16

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