SupremeAir 100% Certified Australian Virgin Activated Carbon Filters are the freshest filters to come out this century! Don't be left with filters that don't fully remove odors. At SupremeAir, we purchase only the premium 20% of any carbon produced. Our onsite Carbon Analysis Laboratory allows us to batch test, de-dust, and hand-pick our carbon. We use the exact particle size required for optimal airflow. Any carbon that is too small, too dusty, or does not meet our stringent air stream tests (minimum 20% butane absorption) is sent back to the manufacturer. What remains is the smallest, lightest, and least restrictive carbon filter canister available, making for easier installation, more airflow, and better air filtration with extended operational life.