Purple BVV Vacuum Pump Activated Carbon Exhaust FilterCarbon Exhaust Filter for BVV Vacuum Pumps Replaces Koby Junior (US Patent# 3169112A) BVV Vacuum Pump Activated Carbon Filter for use with Purple BVV vacuum pumps. Pump Models Include: BVV4D, BVVSF6S, BVVSF6D, BVV7S, BVV9D, BVVSF12D This filter will adsorb contaminants such as oil aerosols, oil vapors, certain other hydrocarbon vapors, and trace moisture. They also trap all foreign solid particles and bacteria down to 0. 5 microns in size. Key