The Irwin 230mm Circular Saw Blade has expansion slots which dissipate heat and prevent warping. Its construction grade tungsten carbide tips retain their edge, and the plate is fully hardened for durability. The blade features alternate top bevel tooth grind (ATB) for cross-cutting and ripping in all woods. Its corrosion resistant coating provides longer quality performance.The IRWIN IRW1897206 Circular Saw Blade has the following specifications:Blade diameter: 230mm.Bore: 30mm.Reduction Ring: 20, 16mm.Teeth: 40.