Key, 4x16 mm 

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

Item No	Models
103	Grizzly G0463 Grizzly Small Mill Harbor Freight 93885 Central Machinery Small Mill Various X3-US SIEG Small Mill Woodstock International M1110 Shop Fox Small Mill
11	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)
130	LittleMachineShop.com 6450 HiTorque Mini Mill
145	LittleMachineShop.com 3900 HiTorque Mini Mill Various SX2L-US SIEG Mini Mill
154	BusyBee CX611 Craftex Small Mill Various SX3 SIEG Small Mill
197	BusyBee CX611 Craftex Small Mill Various SX3 SIEG Small Mill
2.1	Grizzly G8689 Grizzly Mini Mill Micro-Mark 82573 MicroLux Mini Mill BusyBee CX605 Craftex Mini Mill Harbor Freight 44991 Central Machinery Mini Mill Northern Tool 49657 KLUTCH Mini Mill Homier 03947 Speedway Mini Mill Cummins 7877 Cummins Mini Mill Various X2-US-MT3 SIEG Mini Mill Various X2-US-R8 SIEG Mini Mill Bolton XJ-9510 Mini Mill Hare & Forbes HM-10 SIEG Mini Mill Princess Auto 8507667 Powerfist Mini Mill Travers Tools OT2213 OTMT Mini Mill Eastwood 32498 Mini Mill Penn Tool Co XJ-9510-1 Precise Mini Mill Clarke CMD300 Mini Mill Various X2L-US SIEG Mini Mill WEN 33013 WEN Mini Mill
203	Grizzly G0619 Grizzly Small Mill Various SX3 SIEG Small Mill
3	Grizzly G8689 Grizzly Mini Mill Micro-Mark 82573 MicroLux Mini Mill BusyBee CX605 Craftex Mini Mill Harbor Freight 44991 Central Machinery Mini Mill Northern Tool 49657 KLUTCH Mini Mill Homier 03947 Speedway Mini Mill Cummins 7877 Cummins Mini Mill Various X2-US-MT3 SIEG Mini Mill Various X2-US-R8 SIEG Mini Mill Bolton XJ-9510 Mini Mill Hare & Forbes HM-10 SIEG Mini Mill Princess Auto 8507667 Powerfist Mini Mill Travers Tools OT2213 OTMT Mini Mill Eastwood 32498 Mini Mill Penn Tool Co XJ-9510-1 Precise Mini Mill Clarke CMD300 Mini Mill Various X2L-US SIEG Mini Mill WEN 33013 WEN Mini Mill
5	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
7	BusyBee CX612 Craftex Mini Mill Micro-Mark 84630 MicroLux Mini Mill Various SX2-US SIEG Mini Mill
B18	LittleMachineShop.com 5550 HiTorque Bench Mill Various SX2.7L-US SIEG Bench Mill LittleMachineShop.com 6550 HiTorque Bench Mill LittleMachineShop.com 6570 HiTorque Bench Mill
B19	LittleMachineShop.com 5500 HiTorque Bench Mill Various SX2.7-US SIEG Bench Mill LittleMachineShop.com 5520 HiTorque Bench Mill LittleMachineShop.com 6500 HiTorque Bench Mill
C15	LittleMachineShop.com 5550 HiTorque Bench Mill Various SX2.7L-US SIEG Bench Mill LittleMachineShop.com 6550 HiTorque Bench Mill LittleMachineShop.com 6570 HiTorque Bench Mill
C19	LittleMachineShop.com 5500 HiTorque Bench Mill Various SX2.7-US SIEG Bench Mill LittleMachineShop.com 5520 HiTorque Bench Mill LittleMachineShop.com 6500 HiTorque Bench Mill

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