In addition to applying to keys of constant rectangular or square cross-section mounted parallel to the shaft centreline, ISO 21940-32:2012 also applies to keys mounted on tapered shaft surfaces, to woodruff, gibhead, dowel and other special keys. The principle of the half-key convention is applied as is appropriate to the particular shape and location of the special key.
GSO ISO 24157:2013 history
2013GSO ISO 24157:2013 Ophthalmic optics and instruments -- Reporting aberrations of the human eye