ELMERS X-Acto Blades For Utility Knives, 15 Blades Per Pack (X492) Refill blades for utility knives For Ergo Dual Utility Knife (HUNX3276) and SurGrip Utility Knife (HUNX3272/HUNX3274), Also for Quick Change Utility Knife (BOS10499), Interlock Utility Knife (BOS10189C), and Plastic Utility Knife (BOS10065) All sold separately This is an aftermarket of generic part