Husqvarna AM Endurance HSS Blades - high speed steel blades with softer core and hardened edges - pack of 6Husqvarna Automower Endurance HSS blades, high speed steel blades with softer core and hardened edges for extra sharpness and robustness. The Husqvarna Endurance design allows for cutting edges on all four sides of the blade and the new choice of material provides improved cutting properties. Safety blade according to standards. Edge Hardness (HRC) 64 Number of Cutting edges 4 No. Of Blades included 6 Material Carbon steel + HSS