This International Standard defines certain dimensions for the involute splines used for driving power socket wrenches, and for the ends of these sockets.
It covers both the male end dimensions, and the female end dimensions.
The pitch p/ps as given in the tables defines the spline dimensions. The first number, p, is the diametral pitch; the second number, ps, is the stub pitch and denotes, as the fractional part of an inch, the basic radial length of engagement, both above and below the pitch circle. The module, m, denotes the number of units of pitch diameter per tooth, in millimetres.