www.universityofcookie.com :::How to use a disposable piping bag with a coupler and tip
https://www.superiorwasher.com/washers/8910/Rubber-Flat-Washers.html
This video talks about a reliable fastening and sealing hardware used in various applications such as plumbing, household/electronic appliances, industrial equipment and a lot more. This hardware not only cushions fasteners but distributes load, insulates, protects against shock and vibration, tightens and seals and maintains a secure and flexible hold in a bolt and nut assembly — all these are efficiently delivered by rubber flat washers.
Manufacturers of rubber flat washers should have extensive stamping capabilities in order to produce the required quality and efficient performance of the washers according to the specifications and requirements for which they will be used.