What component is held in the access panel by a retaining ring and is furnished in flush and protruding types?

The grommet is the component that is secured in the access panel by a retaining ring and comes in both flush and protruding types. Grommets are used to protect or insulate wiring and other components that pass through a panel, preventing wear from abrasion and environmental factors. The retaining ring holds the grommet in place, ensuring stability and reliability in various operational conditions found in aviation environments.

In flush types, the grommet is designed to sit level with the surface of the panel, while protruding types extend slightly above the panel surface, providing different mounting options based on the application while still maintaining protection. This versatility is crucial for accommodating various components that might be interfacing with the grommet, giving it an essential role in mechanical assemblies.