FAQ

You exhale directly into the PHREND. Inside is our patented Zero-5™ technology, a 5-stage microfiltration system that captures airborne particulates, odor, and toxins as you blow through it. What comes out the other side is clean, filtered air. It traps particles as small as 0.3 microns with 99.75% efficiency.

Each PHREND device is designed for up to 500 exhales under normal conditions. Usage may vary depending on the duration and intensity of each exhale.

When used correctly, PHILTER eliminates virtually all visible output. You should see little to no exhale output, and there should be minimal to no odor.

The PHREND device itself is durable and long-lasting. When the filter is exhausted (after up to 500 exhales), you can purchase replacement PHREND Refills to continue using your device.

Zero-5™ is our patented 5-stage filtration system that combines multiple filter media to achieve clinical-grade air purification in a pocket-sized device. It effectively removes bacteria, viruses, and toxic particulates from your exhale.

Standard shipping within the US typically takes 3-5 business days and is free on orders of $50 or more ($10 flat rate under $50).

We currently ship within the United States only. We do not ship to PO Boxes or APO/FPO addresses at this time.

Once your order ships, you'll receive an email with tracking information. You can also track your order by logging into your account on our website.

Orders can be canceled before tracking information is generated, which is generally within 24 hours of placement. Contact us immediately at support@philterlabs.com if you need to make changes.

Subscribe & Save on the PHREND Refills page and your 2-pack of Zero-5™ cartridges ships automatically every month or every 2 months, your choice, at 10% off the one-time price. Billing runs securely through PayPal, and standard shipping is free on subscription refill orders.

Yes. Cancel your current subscription and re-subscribe at the cadence you prefer. Frequency switching in a single click is on the way.

Pause or cancel from your PHILTER account. You can also cancel at shopphilter.com/subscription with your subscription ID and subscriber email, or through PayPal Automatic Payments. There are no cancellation fees or minimum purchases, and deliveries already paid for still arrive.

Products may be returned within 30 days of delivery. Items must be unused, in original packaging, and in resalable condition. For sanitary reasons, used filtration devices cannot be returned. Defective products are eligible for return within 7 days regardless of use.

Contact our support team at support@philterlabs.com with your order number and reason for return. You'll receive a Return Authorization (RA) number and return instructions. Returns without an RA number will not be accepted.

Once we receive and inspect your return, approved refunds are processed within 5-10 business days to your original payment method. Original shipping charges are non-refundable unless the return is due to our error.