This Standard specifies the Knoop hardness test method for metallic materials, fortest forces from 0.098 07 N to 19.614 N. The method is recommended only for indenta-tions with diagonals ≥ 0.020 mm. NOTE: The International Standards corresponding to this Standard is as fol- lows. ISO 4545-1 : 2005 Metallic materials- Knoop hardness test- Part 1 : Test method ISO 4545-4 : 2005 Metallic materials -- Knoop hardness test- Part 4 : Table of hardness values (Overall evaluation : MOD) In addition, symbols which denote the degree of correspondence in the contents between the relevant International Standards and JIS are IDT (identical), MOD (modified), and NEQ (not equivalent) according to ISO/IEC Guide 21.