ISO 4228:1986

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 is the diametral pitch; the second number is the stub pitch; it denotes, as the fractional part of an inch, the basic radial length of engagement, both above and below the pitch circle. The module denotes the number of units of pitch diameter per tooth, in millimetres.