The Irwin Marples Circular Saw Blades are made from carbide which is larger and tougher than standard carbide for up to 3 times longer life. The teeth can also be re-sharpened. The body of the blade is laser cut to ensure a more straight and clean cut. Precision tensioning provides greater accuracy. The blades have a special coating with aluminium flakes that help to dissipate heat for smooth, cool cuts. The Alternate Top Bevel tooth grind (ATB) is ideal for cross cutting and ripping in all woods.The IRWIN Marples IRW1897475 Circular Saw Blade has the following specifications:Diameter: 250mm.Bore: 30mm.Teeth: 40.