Dewalt 389243-00 1/8" COLLET 
This part replaces obsolete part #:  389243-01
This part is compatible with the following machines:
DeWALTDW660S Type 1 Cut Out ToolDW660S Type 2 Cut Out ToolDW660S Type 3 Cut Out ToolDW660 Type 1 Cut Out ToolDW660 Type 2 Cut Out ToolDC550A Type 1 18V Cordless Cut Out ToolDC550W Type 1 Cut Out ToolDC551 Type 1 Cut Out ToolDW660SK Type 1 Cut Out Tool KitDW660SK Type 2 Cut Out Tool KitDW660SK Type 3 Cut Out Tool KitDC550P Type 1 18V Cut Out ToolDC550K Type 1 18V Cut Out ToolDC550KA Type 1 18V Cut Out ToolDC550P (Type 1) Heavy Duty 18V Cordless Cut-Out ToolDW660K (Type 1) Cut Out Tool KitDW660K (Type 3) Cut Out Tool Kit