Original U.S. Army XM28E4 Riot Control Agent Mask manufactured by Mine Safety Appliances (MSA) in 1969. Developed to meet U.S. military requirements in Southeast Asia, the XM28E4 was a lightweight, low-profile mask intended specifically for protection against riot-control agents such as CS tear gas. Its angular facepiece and large lenses earned it the nickname “Grasshopper.”

The XM28E4 became closely associated with the Vietnam War, particularly tunnel-clearing operations, reconnaissance and MACV-SOG personnel, and some helicopter aircrews. Its flexible construction, internal cheek-filter system, and compact carrier allowed it to occupy considerably less space than a conventional field protective mask.

This Medium example displays matching 1969 MSA markings on the facepiece and valve cover. It includes a correctly marked olive-drab XM28E4 carrier bearing the official designation “MASK, RIOT CONTROL AGENT, XM28E4” and the warning “FOR USE IN RIOT CONTROL AGENTS ONLY.”

Original surplus condition with surface scuffs, lens marks, light residue, and general storage wear. The carrier shows age and handling wear with its markings remaining visible. Please examine all photographs for exact condition.

Sold strictly as a historical collectible or display piece. The mask and its aging filter components have not been tested and must not be relied upon for respiratory protection.