In 1982 the legendary assistive technology company Possum created a range of accessible computers intended primarily for use in UK schools. Amongst these were three special ZX Spectrums: The Desktop Scanning model, the Brief-case Scanning model and the Expanded Keyboard.
The video above was uploaded by David Crockford at Possum from their amazing archive of assistive technology dating back to the 1960s. Read a little more on the Possum ZX Spectrum in the February 1983 ZX Computing magazine. This and much more will be appearing in my book the One Switch 100.