Cumana, a company better known at the time as a BBC micro disk drive supplier, were one of the early hardware companies for the Sinclair QL, releasing their Cumana Floppy Disk Interface in 198x. They traded from Guildford in Surrey.
Interestingly, QLUB News from September/October 1985 talks about them expecting to release an OS-9/68000 environment for the machine (as well as the disk interface) - known as the 'Cumana Upgrade'
The OS-9 environment was to include:
Cuamana did bring out a version of this hardware on a board to act as a co-processor for the BBC (although it is unclear if this ever went into production).
I wonder what happened to the QL version?
Cumana are still in business, concentrating on IT for schools - visit the Cumana website