MSA All-Vision Chemical Cartridge Respirator
The MSA All-Vision Gas Mask was made for a variety of applications, including law enforcement and industrial use. This configuration was called the All-Vision Chemical Cartridge Respirator. It had two cheek exhale valves and a filter canister attached directly to the chin to protect against tear gas. This example was made by Mine Safety Appliances in 1969.
Similar masks in my collection: MSA All-Service Diaphragm Chemical Cartridge, MSA All-Vision Acid Gas, MSA All-Vision Organic Vapors, S&W All-Vision Diaphragm Chemical Cartridge, Acme Full-Vision No. 6, German Kareta-Nova