Two magnetic reel tapes with 1600BPI. BPI stands for bits per inch and it specifies the data density that a magnetic reel can hold.
References: http://en.wikipedia.org/wiki/BPI
These are video upgrade cards for the Apple Macintosh. They were created in 1992. Supermac was later acquired by Umax.
References: http://en.wikipedia.org/wiki/Supermac