What are the four principal parts of a quick-release design fastener used on panels?

The correct answer identifies the four principal parts of a quick-release design fastener used on panels: receptacle, grommet, retaining ring, and stud assembly.

In the context of fasteners specifically designed for quick-release mechanisms, the receptacle acts as the housing or socket into which the stud is inserted. The grommet provides a sealing function that protects the fastener from environmental elements and potential wear. The retaining ring is crucial for keeping the stud securely in place once it is inserted into the receptacle, preventing accidental disengagement. Finally, the stud assembly is the component that inserts into the receptacle, allowing for a quick connection and disconnection.

Understanding these components is essential in applications where efficiency and ease of access to panel installations are required, such as in aircraft maintenance and repair.