The famous ultra rare Wafadrice from Rotronics.
The Rotronics Wafadrive is a magnetic tape storage peripheral launched in late 1984 for the ZX Spectrum home computer. Each tape is a continuous loop, unlike cassette tape. It was intended to compete with Sinclair's ZX Interface 1 and ZX Microdrive.
Tested and working perfectly. See pictures. However the cartridges worked for two reads each and then they cut the tape.
Sold as-is.
If you manage to find cartridges then you are on for a hell of a ride as this wafadrive works ok.