Washer, M8 Lock 

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

Item No	Models
106	LittleMachineShop.com 6450 HiTorque Mini Mill
121	LittleMachineShop.com 4829 Band Saw
126	LittleMachineShop.com 4829 Band Saw
3	LittleMachineShop.com 4660 HiTorque Micro Mill LittleMachineShop.com 4700 HiTorque Micro Mill
48	LittleMachineShop.com 3960 HiTorque Mini Mill LittleMachineShop.com 3990 HiTorque Mini Mill LittleMachineShop.com 4190 HiTorque Mini Mill Various SX2LF-US SIEG Mini Mill LittleMachineShop.com 4962 SIEG Mini Mill (X2D)
7	LittleMachineShop.com 4829 Band Saw
A015	LittleMachineShop.com 6700 HiTorque Large Bench Mill LittleMachineShop.com 6750 HiTorque Large Bench Mill Various SX3.5-US SIEG Large Bench Mill LittleMachineShop.com 6770 HiTorque Large Bench Mill

Click your model to see the complete parts list.