DerBlue 4-Pcs Replacement Filter for Holmes AER1 | Compatible with 300AH-U4R & HAP242-NUC

Overview

Transform the air quality in your daily spaces with DerBlue’s 4-piece replacement filter set. Engineered to fit a wide range of Holmes and Bionaire models, these filters are designed for a snug, precise fit and dependable filtration. The result is smoother airflow and a sense of freshness in rooms you spend time in—whether it’s a living room, a home office, or a cozy bedroom.

Rather than a single-use part, this four-pack offers reliable value and a consistent replacement cadence. The filters are crafted to withstand regular operation and help maintain steady performance as you go about your day. While results can vary by environment, many users notice a noticeable improvement in air feel after installation, especially in spaces with shared air or seasonal dust loads.

What’s in the box

• Four filters (each approx. 10 x 4.6 x 1.37 inches)
• Replaces Filter A, Filter D, and Filter K
• Durable construction designed for extended use
• Ready-to-install compatibility with select Holmes and Bionaire units

Compatibility at a glance

• Holmes units: CAP531-U, CAP529-U, HAP240, HAP242, HAP412, HAP422, HAP424, HAP706, HAP716, HAP9240, HAP9242, HAP9412, HAP9414, HAP9422, HAP9424, HAP1200
• Bionaire units: HAP412, HAP422, HAP424, HAP702, HAP706, HAP716, HAP1702, HAP2400, HAP9240, HAP9241, HAP9242, HAP9243, HAP9412, HAP9413, HAP9414, HAP9415, HAP9422, HAP9423, HAP9424, HAP9425
• Additional compatibility: BAP260, BAP520, BAP815, BAP825, BAP9200, BAP9417, BAP9427, BAP9435, BAP9700

Durability and value

• Durable materials engineered for long life and steady filtration
• Four-pack provides ongoing convenience and cost savings
• Support from a responsive customer team for compatibility questions or guidance

Note: For best results, aim to replace filters every four months, adjusting for usage and environment. If you have questions, our team is ready to assist you for a smooth, hassle-free experience.