Filter-Monster Replacement Compatible with Whirlpool 8171433K Pre-Filter for Whirlpool Air Purifier Models AP25030K, APR25130L, APR25530, AP150, AP250, 4 Pack

Air Quality Improvement: Activated carbon helps reduce household odors such as cooking, cleaning and pet odors | Maintenance: Recommended to change every three (3) months, or more often in harsh environments, for maximum efficiency | Approximate Dimensions: 16 1/4 x 11 3/4 x 1/8 inches | What You Get: Four (4) Pre-Filters