It looks like this Part has been superseded by LEGO Part 26674 Pneumatic Pump 1 x 6 [V2] with Reinforced Cylinder.
Click on a colored part below to see the Sets and MOCs that use part 19482 Pneumatic Pump 1 x 6 with Stepped Outlet [V2] 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.