The Macintosh Plus Keyboard is a pointing device that was designed, manufactured, and sold by Apple from 1986 to 1990 as part of the Apple Keyboard series. The Keyboard has been introduced on January 16, 1986, alongside the Macintosh Plus.
The new keyboard debuted with an integrated numeric keypad. It used a telephone cord-style RJ-11 connector to the case.
This keyboard has been discontinued on October 15, 1990.
Today Macintosh Plus Keyboard is 37 years old!
Source: vectronicsappleworld.com – Apple Macintosh Plus Keyboard