Zico ZI-4055 25mm/1-Inch Heavy Duty Snap-off Utility Knife Bledes, 10-pack Heavy duty, 25mm / 1 inch blades width Excellent for cutting drywall 10 Pack, in hard plastic dispenser Made of SK-5 alloy steel Use 25mm / 1-Inch ZICO ZI-4025 Knives with these blades