This International Standard specifies requirements for blades used on rotary disk mowers and rotary drum mowers, mounted, semi-mounted, trailed, or self-propelled, as used for forage crop harvesting in agriculture only. It specifies requirements for testing and marking of such blades. NOTE 1 The main purpose of this International Standard is to set material characteristics. Blades on agricultural rotary mowers are exposed to considerable centripetal forces and impacts with foreign objects. A bend test and impact test to check the brittleness and toughness of the material is therefore included in this International Standard. NOTE 2 This International Standard does not specify dimensional requirements.