P/N UB4L4HA
More about this type of keyboard...
The Enhanced Keyboard was the first home consumer, most common and the definitive Model M keyboard, becoming IBM's choice keyboard for a decade after its release and still in production today as the Unicomp Classic. Labelled as being "enhanced" in regards to its layout that became an industry standard and still used today with the addition of GUI keys, the Model M is perhaps the most well-known keyboard of all time thanks to the success of the Enhanced Keyboard and its main host system - the IBM Personal System/2 series. The Enhanced Keyboard was also made available for IBM's earlier "classic" Personal Computer series in both XT and AT flavours, and several other distinct variants exist for other types of systems and custom orders from third-party companies such Dell, Sabre and General Electric.