Ministry Of Defence
Nuclear Weapon Effects Computer
This calculator is for calculating damage to structures,
casualties in various types of structures,
and crater size by weapon power.
Manufactured by: B.R.L.(Blundell Rules Limited) of England
Still operating as Blundell-Harling Limited
Rear View With Instructions For Use.
This unit is marked B-R-L Weymouth, England
This would put it's manufacturing date between January 1956 and January 1964,
when the company became Blundell-Harling Limited.