Bosch P3943WS Workshop Particulate Cabin Air Filter

The Bosch P3943WS Workshop Cabin Air Filter is specifically engineered for professional installers dedicated to helping customers breathe cleaner, healthier air. This particulate cabin air filter features advanced multi-layer filtration technology that captures up to 99% of dirt, dust, pollen, and other environmental contaminants at 3 microns or greater, preventing them from entering your vehicle's heating and air conditioning vents.

Advanced Multi-Layer Filtration Technology:

• First Layer: Non-woven pre-filter captures larger particles like dust and debris
• Second Layer: Electrostatically charged microfiber layer attracts and holds smaller, more elusive particles
• Third Layer: Non-woven cover layer provides stability and protection while acting as an additional barrier to harmful elements

Professional-Grade Features:

• High pleat count design provides greater surface area for superior filtration capacity and longer service life
• Foam perimeter gasket or rigid frame (where specified by OE) ensures proper seal and prevents particle bypass
• 99% filtration efficiency at 3 microns or greater; captures up to 80% of particles under 3 microns
• Direct replacement design for easy installation

Cabin air filters should be inspected at least once a year, though Bosch recommends following your vehicle manufacturer's specified replacement intervals. If you drive in heavy traffic or dusty conditions, more frequent replacement may be beneficial. Signs that replacement is needed include reduced airflow through your HVAC system or unusual noise from the ventilation fan.