The Spectrum +3 was designed to load & save to its 3" disk drive, so leads to allow program loading from a cassette player can be hard to come by. These leads are brand new and allow the connection of a standard tape recorder to the "TAPE/SOUND" socket of the +3. Software can then be loaded from cassette.
Connect the "stereo" plug to the +3 and the "mono" plug to the tape player.
Use if you only want to load from cassette (save to disk).