The ZX Spectrum was an 8-bit home computer made by Sinclair Research Ltd for the UK market, selling over 5 million examples from 1982 to 1992.
Most software was released on Compact Cassette, although alternative systems such as Sinclair’s own ZX Microdrive and the Wafadrive were available early on. In 1983, Sinclair released the ZX Interface 2, which provided 2 joystick ports, a ROM cartridge slot, and a pass-through port for the ZX Printer.
The use of ROM cartridges allowed for instant loading of games, but despite this only 10 cartridge titles were released due to lack of demand. They were more expensive than cassettes, and all the titles were also available on cassette. The last retail titles were released in December 1983.
The red rubber skirt on a ZX cartridge is designed to protect the edge connector contacts and folds out of the way when the cartridge is inserted.
When the ZX Spectrum +2A and +3 models were introduced in 1987, the ZX Interface 2 would no longer work.