ISO 7388-3:2013 specifies the dimensions of retention knobs for tool shanks with a 7/24 taper of shank forms A, AD, AF, UC, UD, UF, JD, and JF for automatic tool changers used on machines having an automatic gripping system for feeding tools from the magazine to the spindle and vice-versa. These tools are designed with the most important dimensions for use in spindle noses according to ISO 9270.