In construction, long self-drilling screws are frequently employed in roofing, cladding, and framing applications due to their strength and ease of use
Jiri George Drobny, in Fluoroelastomers Handbook (Second Edition), 2016
One way to recognize an improperly installed seal is by checking whether or not there is uneven shearing of the rubber after use. If this is evident, adjust by aligning the installation tools properly before pressing the seal into place.
6, the seal is cheap.
Metal case The metal case provides rigidity to the seal, helping it settle on the housing securely. It also ensures easy seal handling and mounting.
Different Types of Oil Seals

An oil seal type that is resistant to oils, fuels, and solvents, fluorosilicone also offers temperature stability. Primarily found in aerospace fuel applications and automotive fuel emission control, this o ring material is fast becoming popular in more and more oil-based applications across a wide spectrum of industries.

Choosing the right oil seal
As type C with dust lip