D-Series Breathers feature numerous models in a variety of sizes, all designed to satisfy the requirements of most stationary fluid management applications. The breathers provide application flexibility by using 100% silica gel for moisture adsorption, 100% activated carbon* for fume and odor control or both, when necessary. All D-Series models feature 2-micron solid particle filtration and are available with airflow ratings of 20 cfm.

The D-Series is constructed of industrial grade raw materials, tested to ensure a wide range of chemical compatabilities, and features high impact resistant ABS top and bottom caps. The clear acrylic tube makes it easy to inspect the condition of the colour-changing silica gel from a distance. The silica gel turns from gold to dark green to visually indicate the adsorption of moisture and confirm the breather is getting the job done!

All Air Sentry® raw materials have been tested to ensure chemical compatibility with a wide range of industrial lubricants, fuels and fluids. 

 * Carbon filters are special orders; please contact us for more information


Disposable and Stationary Applications


Oil Storage Tanks • Fluid Reservoirs • Transformers • Pumps • Gearboxes

Base Material:

100% Silica Gel

Max. air flow/fluid flow:

20 cfm / 150 gpm. 

Mounting connections:

Slip fit, 1”MNPT, 2” MNPT, 3”MNPT 


5" and 6"


3.5" to 14"



  • Protects expensive equipment
  • Ideal solution for fluid contamination problems
  • Filters damaging particles
  • Reduces other contaminates
  • Blocks corrosive water vapor
  • Disposable- replace when desiccant colour changes from gold to green
  • The D Series easily replace the standard vent / filler cap.
  • 8 standard models
Air Sentry Guardian breathers
d-series breather specification
Guardian breathers
High capacity air filter
Breather X-Series