I posted this question to Ariens tech support: According to Ariens 21 pro manuals, Ariens made two blades for the 911 series: 01137000 (Standard) 01182400 (Tungsten) I want to order some additional tungsten blades, but no one online seems to have them--not when I search by the part number, nor when I search for Ariens + 911000 + tungsten. Is the tungsten blade still available? If so, who sells it? Ariens to me: Dear Paul The tungsten blade, part number 01182400 is no longer available. Thank you Tom Dvorachek Customer Service Rep Ariens/Gravely Co. So: Which high-lift blade do you guys recommend? Oregon?