Not sure what you are asking about.............
The air cylinder came with two end plates on it, and uses long stud bolts to hold those onto the cylinder.
The solonoid has two "mufflers" installed on it, which quiets the exhausted air pressure.
Those were covered in another thread. They make them in sintered bronze and plastic. Either one works well enough, the plastic version is much cheaper.
http://www.automationdirect.com/adc/...aust_Silencers