Philips Respironics Reusable Foam Filters for Tranquility Quest, Quest Plus, Auto and BiLevel Machines - 5 Pack

DIMENSIONS: Approximately 4.25 x 4.50 inches with a slightly curved rectangular shape.

USAGE: For optimal performance reusable filters should be washed weekly and replaced every 2-3 months or whenever they appear worn or damaged. For complete instructions review the documentation that came with your equipment.