Disposable in-line field filter, standard capacity, (30 cm2), 0.45 micron pore size.
Amazon.com: CPAP Filter– Premium Ultra Fine Disposable Replacement Filters for CPAP Machines – Compatible with ResMed Air 10, Airsense 10, Aircurve 10, S9 Series and More! 30 Filters : Health & Household
Tetra Whisper Bio-Bag Disposable Filter Cartridge 3 Count, for Aquariums, Large - Walmart.com
FIBERGLASS DOUBLE STRUT DISPOSABLE FILTER – A & R Supply
DreamStation Disposable Ultra Fine Filters : Ships Free