Check the listing for details. RZ Mask & Extra Filters, Replacement F1 Standard + Active Carbon, Large,. Color: Gray, Condition: New. Listed at 15.99 USD. Fast & Free Shipping!!! Product Overview: The F1 Active Carbon Filter is stocked in all masks and features a 99.9% efficiency rating down to 0.1 micron. It's effective towards dust, fumes, allergens, smoke, odors organic chemicals and more. The filter has a long lifespan allowing the user to save costs and create less waste over time compared to disposables. This pack contains 3 replacement filters and fits a medium mask.What's Included: Includes (3) replacement filters (3 Boxes, 9 Filters in this offer)Common uses low intensity, fumes and odorsConsists of two filter layers- the outer particulate filter and the internal active carbon elementTraps particulates as small as .1 micron in size20-30 hours of continuous use with heavy dust exposure to things such as grain bins, off-roading, construction/demolition, etc30-40 hours of continuous use with light dust exposure to things such as grain bins, off-roading, construction/demolition, etc50-60 hours of continuous use when protecting against allergens, pollutants, odors, etc Specifications: What's Included: Mask and a total of 5 FiltersBrand Name: RZ MaskProduct Type: Replacement Active Carbon FilterBrand Name: RZ MaskColor: GRAYPackaging Type: BoxedQuick Release: YesRespirator Type: Multi-PurposeReusable: YesSeries: F1Size: LAdjustable Nose Clip: YesFiltration: 99.9 percent ***Buyers note!***I work with wood, stone, diatomaceous earth and have used this brand for over 6 years. They work great for what I do.