This document describes the design, assembly force, and packaging guidelines for conventional hand-plug, mechanical assist and twist lock electrical connectors, as well as Connector Position Assurances (CPAs). All possible designs and applications could not be anticipated in creating these guidelines. Where there are questions of adherence to this document, such as use of an Â¿off-the-shelfÂ¿ design, always consult the responsible Ergonomics Department. Refer to SAE/USCAR-12 Wiring Component Design Guidelines for additional guidelines.