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Rockwell International is a U.S. company.

Most Rockwell calculators were labelled "Assembled in Mexico.  U.S. and Foreign parts" or "Made in Hong Kong", but a few are found labelled "Made in Great Britain".

Models known to have been manufactured in Britain :-


Rockwell had bought the British calculator manufacturer Sumlock Anita Electronics Ltd. and the distributor Sumlock Comptometer in 1973.  The name of the distributor was changed to Sumlock Anita Ltd.

Some examples of some of the Rockwell models were manufactured at the Sumlock Anita Electronics factory at Portsmouth, Hampshire.  A company internal memo of October 1974[1] lists the Rockwell calculator models that the company will be dealing with after the takeover and says "For the first few months we will import machines from the U.S.A. but active steps are now being taken to ensure that production of this new calculator range will commence at Portsmouth early next year".

Management in Action, in December 1974[2] reported on the Rockwell Answer range of calculators:
"Rockwell International, ...   ..., is entering the British domestic market with a range of five calculators from a pocket model to advanced machines for engineers and scientists. ...
The machines are named Answers.  The company reckons to transform the rapidly developing calculator market by selling a full range of easily recognisable, reasonably priced machines, backed up with nationwide servicing. ...   ... For example, the tiny [Rockwell] Answer 51R is a general-purpose calculator and an automatic converter from British to metric measurements, holiday currency conversions and sums involving fractions. ...   ... The price is £55.95 including VAT.
Answers will be manufactured at the Portsmouth, Hants, factory of Sumlock Anita Ltd, the British subsidiary of Rockwell. ..."

The logo "Answer" was marked on the box but not on the calculator and may have been used just for the British market.


Rockwell also manufactured some models at the Portsmouth factory for House of Fraser, a British department store chain.  These can be found on the House of Fraser page.


  1. "Information Bulletin: Pre Product Release Information, Rockwell Consumer Range, 10R, 20R, 30R, 51R, 61R", Sumlock Comptometer Limited internal memo, section 1.0, 29th October 1974.
  2. "New Products: Answers", Management in Action, December 1974, p27.

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