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. Negative rake blades are best used in machines where you pull the blade towards you as it helps to prevent from self feeding.The IRWIN IRW1897429 Construction Circular Saw Blade has the following specifications:Diameter: 254mm.Bore: 30mm.Reduction Ring: No.Teeth: 60.