Contains an Antimicrobial Treatment by MicroFree to prevent growth and migration of mold, fungus, algae, and bacteria.  Also features durable construction for maximum life and humidity output.

Replace your filter every 4-6 weeks for best performance and comfort

Fits Humidifier Models:  110, 220, 550, 550A, 558

Aprilaire Replacement Humidifier Part Numbers: 10

RPS BestAir Replacement Part Numbers: A10-W

Approx. Measurements: 9 1/2" x 9 3/8" x 1 7/8"

Please Note:
These Filters are Replacements Manufactured by Best Air RPS Products. Fit and Function are Backed With a 30-day Money Back Guarantee.