AIR FILTER FOR DOGS: As seen on “Shark Tank” season 12 episode 6 in 2020. | MADE IN USA: Designed in Austin, Texas and made by craftsmen in Dallas, Texas. | INCLUDES (3) ‘EXTREME BREATHE’ AIR FILTER REFILLS: Filters micro particle PM2.5 like smoke, pollen, ash, dust, soot, and ozone. | EFFECTIVE POLLUTION FILTERING: Two adjustment straps for the neck and snout to maximize filtering effectiveness. | PREPARING YOUR DOG: Your dog may require 1-3 weeks of training in preparation for wearing the K9 Mask. Review K9 Mask instructional training videos on our website.