Nut, M8 

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

Item No	Models
338	LittleMachineShop.com 4959 SIEG Mini Lathe - 7x14 (C3) Various C3-US SIEG Mini Lathe - 7x14
63	LittleMachineShop.com 4959 SIEG Mini Lathe - 7x14 (C3) Micro-Mark 82710 MicroLux Mini Lathe - 7x14 Various C3-US SIEG Mini Lathe - 7x14
79	LittleMachineShop.com 4829 Band Saw

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