Ingersoll Rand P4FS-6 Air Reciprocating Saw Blades - Bi-metal saw blades enhance overall cutting performance. Bi-metal technology is a solid state diffusion process that applies high speed steel to both edges of the backing material, increasing the blade contact area by 170%. This, along with a new tooth profile that generates smaller, but more chips, reduces the frictional heat that is generated during the cutting process, which will enhance the overall blade performance. *Ingersoll Rand saw blades can be used with all standard 1/2" shank air reciprocating saws.