The GEC Photo-Electric Exposure Meter was sold by Johnsons during the late 1940s and into 1951. Thereafter, it seems to have been 'dropped' in favour of the Johnsons rotary exposure calculators.

The small (65mm square) instruction booklet can be downloaded as a pdf, click here, courtesy of Peter Davies.

Peter has also made available a shortened form of the instructions, downloadable as a pdf here.