SAE J 1231
This SAE Standard provides general and dimensional specifications for formed tube ends and hose fittings. These connections are intended for general applications in low pressure automotive and hydraulic systems on automotive, industrial, and commercial products. The fittings shown are intended to be retained by hose clamps as specified in SAE J1508.It is recommended that where step sizes or additional types of fittings are required, they be designed to conform with the specifications of this document insofar as they may apply. The following general specifications shall supplement the dimensional data contained in the tables with respect to all unspecified detail.