This part of ISO 9270 specifies the dimensions and tolerances of 7/24 taper spindle noses with tenons for automatic tool changers, intended for use with the corresponding tool shanks of forms A, AD, AF, U, UD and UF, according to ISO 7388-1.
GSO ISO 9270-1:2016 history
2016GSO ISO 9270-1:2016 7/24 taper spindle noses for automatic tool changers -- Part 1: Dimensions and designation of spindle noses of forms S and SF