Irwin Construction Circular Saw Blades have welded carbide teeth for a stronger tooth bond and longer life. The ultra compact carbide is up to 70% tougher than standard carbide for superior sharpness and cut quality.The blades have innovative heat vents and a fully hardened plate that runs truer for longer and with more accuracy. They have an alternate top bevel (ATB) tooth grind for cross cutting and ripping in all woods.The IRWIN IRW1897427 Construction Circular Saw Blade has the following specifications:Diameter: 250mm.Bore: 30mm.Reduction Ring: No.Teeth: 80.