
Gas detector with yellow enamelled metal case. Dial showsa single non-linear scale indicating 0-100% gas
1970-1980
1970-1980
1965-1975
1965-1975
circa 1991
circa 1985
1965-1975
1960-1969
1970-1980
1960-1970
1970-1980
circa 1985
1965-1975
1970-1980
1965-1975
1982
1970-1980
1955-1965
1969