Cover, Nylon, Wiring Hole 

Bottom View

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

Item No	Models
D18	LittleMachineShop.com 6570 HiTorque Bench Mill
D45	LittleMachineShop.com 6500 HiTorque Bench Mill LittleMachineShop.com 6550 HiTorque Bench Mill

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