1.1 This standard specifies dimensions of square cores or inductors made of magnetic oxides and having compatibility with 2·54 mm printed wiring grid.
1.2 This standard also lists preferred sizes of square cores together with their dimensions as far as these are of importance for mechanical inter-changeability.
IS 7934-1981 history
1982IS 7934-1981 Dimensions of square cores made from magnetic oxides and related components