This document is an extension of the current 892.1 standard. It does not supersede the 892.1 standard. Allsplines currently meeting the requirements of the 892.1 standard are still in compliance with that standard. Atable of the variables and the formula that calculates its value is included. Splines conforming to 892.1 will matewith splines conforming to 892.1 b. Splines conforming to 892.1 shall be used unless 892.1 b is specified orotherwise agreed to by the purchaser and the supplier. This addendum does not apply to major diameter fitsplines.Units of Measurement Linear dimensions are expressed in inches, and angular dimensions are expressed indegrees.