The thicker item you want to cut, the thinner saw blade should be. It is suggested that use #1, #2, #3 saw blade to saw the metal; #4 #5 #6 #7 is suitable for wood sawing; #8 can be applied on sawing plastic. Sharp tooth resists loading and improves cutting speeds. Forged from high carbon steel, through fine process, with high hardness and strength. This package is a total of 12pcs saw blade, convenient to replace the broken or worn one. Curve sawing is very relaxed, the blade is not stuck. Saw Blades Set: Different Size Blads for different Usage: Cutting thicker item that should use thinner saw blade. It is suggested that use #1, #2, #3 saw blade to saw the metal; #4 #5 #6 #7 is suitable for wood sawing; #8 can be applied on sawing plastic. Material : Forged from high carbon steel, through fine process, with high hardness and strength. High stability, strong structure and very practical. Useful and Powerful Tool: The Sharp tooth resists loading and improves cutting speeds. Can be