Makita 4/6 variable pitch teeth cut faster DESIGN : Extra hard high speed steel teeth DURABILITY : Flexible, shatter resistant steel body for long life VERSATILITY : For use drilling holes in steel and wood INCLUDES : 1-3/8" Bi-Metal Hole Saw About Model Makita Hole Saws feature bi-metal construction for longer life. The flexible steel body and the high speed steel teeth combine for more efficient cutting. These versatile saws cut through both metal and wood and have the deep cutting ability to go through 2x4 material.