Universal Fit Odor Filters: Perfectly sized at about 3.15x3.15 inches. Safe Material: This activated carbon filters are made of high-quality activated carbon as the adsorption material, and the polymer binding material is used to attach the carbon to the fiber, they are environmental friendly, tear- and safe to use. Quick Replacement: Replace your old filter with a new one in seconds, so you can enjoy an odor-free space. Continuously Fresh: In of 12, each filter provides up to two months of powerful odor-absorbing action for long-term freshness.