Heavy duty hooked trimming knife blades to fit all types of Stanley, Dolphin, Allegro, Shark and other makes of hand tool. Used by industry professionals in roofing, flooring, warehousing, subcontract packing, DIY, crafts, graphic arts and for many other uses. They are stamped 'Heavy Duty', 'Made in Sheffield'. Manufactured in hardened and tempered carbon steel, these razor sharp heavy duty quality blades are designed to withstand the most arduous materials and tasks. The blades are lightly oiled and are packed in cellophane wraps of 5 pieces.