These Bi-Metal Matrix blades with Variable Pitch Teeth have a high speed matrix cutting edge， electron beam welded to a low alloy shock resistant back and resist heat in excess of 1000 degrees F. They cut faster， last 10 times longer than carbon flex back or hard back and have excellent shock and abrasion resistance. Variable Pitch Teeth vary in size， set and gullet depth which brings teeth into the work at constantly changing angles for fast， smooth and quiet cutting. The varying gullet sizes allow increased protection against tooth strippage when cutting on a wide range of materials and/or dimensions.