This kit includes M3 replacement knob and wire lace for easy lace system replacement in the field. This kit is for 1st GENERATION RIVERTEK™ BOA® BOOTS that are no longer sold on this site. If you are buying RIVERTEK™BOA® BOOTS today, do not order this repair kit. Please order M2 BOA® FIELD REPAIR KIT. For the G4 Boa® Boot, please order the G4 Boa® Replacement KitTo Verify which RiverTek™ Boa® Boot you have:Look inside the boot on the tongue label where the size is marked. 2nd Generation boots will state "Boa M2 Reel" and the lace length, 1st Generation boots state only "Boa" and lace length.