Transform your gas mask into a reliable, fully functioning multiuse smoke hood with these VK-450 filters. Designed to overcome smoke & particulates (along with high concentrations of carbon monoxide), these advanced filters provide crucial hours of protection and clean air from some of the most common disasters faced by US citizens. Grab a few VK-450 filters for your family today! Key Features: Proven design provides comprehensive protection from a wide range of NBC threats, smoke and particulates. Smoke respirator mask filter can be used in environments with as little as 19.5% oxygen. Can be used at temperatures ranging from -40Adeg? to +40Adeg?. Prot Mfg: Mira Safety