This is a typical mid-1970s calculator, and can be compared to the Commodore 776M also in the collection. The 887D is a very similar calculator in many ways though noticably wider.
That extra girth allowed for an eight digit red LED display. The calculator was powered by a Commodore GRBP-89 CPU. As well as the four standard operations and percentage the calculator also had an Exchange key (EX) which reversed an operation. My 887D still has it's box, though fairly worn. The box has kept the calculator in good condition though.
