Mindman MSLC pneumatic brass adjustable silencer throttle valve, made from solid brass with a sintered bronze cone element.
Every pneumatic valve that has an exhaust port requires a silencer for a number of reasons. Such as removing harsh valve exhaust noise and removing opportunities for contamination in exhaust ports when not in use.
Additionally the use of an adjustable silencer allows for controlling the speed of exhausting air and slowing motion in a system.
For example, when used on an air suspension valve these can actually slow the dropping speed of the entire vehicles air suspension.