Silicone coat allows the blade to slice easier through material reducing pitch and resin buildup when cutting pressure-treated lumber. Construction-grade carbide teeth deliver longer blade life. Every other tooth is thinner for faster cuts. The innovative heat vent/expansion slot design reduces vibration for longer life and straighter cuts. Plate is fully hardened to run truer, longer. 40 tooth count blades are ideally suited for trim and finish jobs. IRWIN Tools MARATHON Carbide Corded Circular Saw Blade, 7 1/4-inch 40T (24031)