Programmable RPN calculator, Over 250 solutions with 6 keypads: Standard, Engineering, Binary, Magnetics, Trig, and Convert. You can select Fixed, Scientific, or Engineering notation and Degrees, Radians, or Grads for your calculations. Has a running tape display 15 discrete calculators for the more complex functions, and 24 storage registers that you can rename. Has the easy to learn RECPL (RPN Engineering Calculator Programming Language).