It looks like this Part has been superseded by LEGO Part 47223b Pneumatic Switch with Pin Holes and Stepped Outlets [V2].
Click on a colored part below to see the Sets and MOCs that use part 47223a Pneumatic Switch with Pin Holes in that color. You can find an overview of all LEGO Colors here.
If a color is missing, it probably needs to be added to a Set Inventory.
This part has been used by MOCs in the following colors but not officially released.