price: 14.99 GBP platforms: Spectrum
Interface 2 style cartridge slot
Initially there were just 10 cartridges released back in 1983/4 but there have been third party ones since.
Compatible with all models of ZX Spectrum. There's a small switch on the interface to select the type of computer, which can be set as: 16K/48K/128K/+2 or +2A/+2B/+3
Also has a reset button.
Find out more / buy at: https://www.ebay.co.uk/itm/ZX-ROM-CARTRIDGE-SLOT-for-the-ZX-SPECTRUM-NEW-from-Quazar/114240952078?hash=item1a994a970e:g:G4IAAOSw00Be0NYk&mkcid=1&mkrid=710-53481-19255-0&siteid=3&campid=5338662899&customid=&toolid=10001&mkevt=1