260 and 261 Church Road

Engineers

Source:
Borough of Mitcham List of Factories,
Town Clerk’s Department,
July 1963.
Available at Merton Heritage and Local Studies Centre at Morden Library.
Reference L2 (670) MIT

History of the company, from its website in 2016:

1921 Rototherm invents bi-metallic thermometer
1934 moves to factory in Merton Abbey
1969 moves to new factory in Port Talbot, Wales

See also Grace’s Guide.