These replacement blades are meant to be used for the No. 4 and 5 of the Busy Bee line of planes. They are made from O1 steel are hardened to 58-62 HRC can also be used in most vintage Stanley-type planes. Whether you have used-up a blade or want a second blade to sharpen differently, these blades will defiantly fit the bill.
FEATURES
Made from O1 steel that takes a fine edge Hardened to 58-62 HRC