Filter inside low flow modules 800518 & 800519 Back Catalog number: 201119 Manufacturer: SENSIDYNE Availability: In the manufacturer's stock Price on request - + Recommended 811-9927-06 Cyclone, GK 2.69 25mm O-Ring Kit Price on request 385-0115-01 Nephelometer O-Ring, Replacement Price on request 911-9901-EU-R Single Unit Charger w/ Power Adapter, USB GilAir-3 Price on request