These blades are made from sheffield steel to the highest quality. They are double sided and can be easily flipped over for a new blade installation. This hooked blade has a standard hook. Quick and easy cutting waste when sizing. Also used for cutting in vinyl sheet. The blade has two knotches and fits all the standard utility knives in the trade. Wrapped in 5’s into boxes of 100. Fits the Delphin knife, Stanley knife, shark knife and all standard utility knives.