Specifies requirements, additional to those in E35.1 for all seat belt assemblies, for assemblies with manual length-adjusting and unlocking retractors, automatic length-adjusting and locking retractors, and emergency locking retractors. It includes fail-safe provisions and prescribes tests for durability of mechanism, corrosion during durability test, dust during durability test, locking, emergency locking, and withdrawal and retracting forces.