The item include 5pcs, as same as picture,4pcs of collets, and 1pcs of nut . The collets are 1pcs of 1/8" ,1pcs of 6.0mm,and 2pcs of 1/4". It fits to Dewalt DW660S Type 1 Cut Out Tool,DW660S Type 2 Cut Out Tool,DW660S Type 3 Cut Out Tool,DW660 Type 1 Cut Out Tool,DW660 Type 2 Cut Out Tool,DC550A Type 1 18V Cordless Cut Out Tool,DC550W Type 1 Cut Out Tool,DC551 Type 1 Cut Out Tool,DW660SK Type 1 Cut Out Tool Kit,DW660SK Type 2 Cut Out Tool Kit,DW660SK Type 3 Cut Out Tool Kit,DC550P Type 1 18V Cut Out Tool,DC550K Type 1 18V Cut Out Tool,DC550KA Type 1 18V Cut Out Tool,DC550P (Type 1) Heavy Duty 18V Cordless Cut-Out Tool. It also fits to DW660K (Type 1) Cut Out Tool Kit,DW660K (Type 3) Cut Out Tool Kit,DCS551B (Type 1) 20v Crdls Cutout Bar,DCS551B (Type 2) 20v Crdls Cutout Bar,DCS551D2 (Type 1) 20v Cordelss Cutout Palm Router. Please Note: May not fit all specs of above models listed, please consult owner's manual for proper part number identification and proper installation. Please kindly check the size of the collet you need or if you have any questions,welcome to contact us before ordering. It is an authentic item that allows user to secure bits. Please note, this collet is for using bits with 1/8" ,6.0mm 1/4" arbors . It is made from durable metal and is sold individually. The collet nut that is used to secure this part is sold separately. You will need a wrench when replacing this collet.