Specifies interchangeability dimensions for agricultural disks of the same type and nominal size, classified as types A, B, and C. Applies to disks as working parts of ploughs, harrows, and disk-tillers. Tabulates concave disks type B, variant 1 and 2, and type C (table 1), type B, variant 3 (table 2), and tolerances for eccentricity and wobble of disk types B and C (table 3). The figures 1 to 4 illustrate profiles and sections.