Spyder Mach-Blue coated reciprocating saw blades feature 8% cobalt bi-metal construction for increased durability in tough applications. Super hard Mach-Blue plating retains sharper cutting edges, and reduces heat build-up and cutting friction - yielding up to 20x more cuts than conventional bi-metal blades. At a fraction of the price, these Mach-Blue blades represent an extreme value when compared to drastically more expensive carbide tipped reciprocating saw blades. Spyder Mach-Blue coated reciprocating saw blades are made in Germany.