Made from waterproof plastic material, Built-in scale, more lighter, smaller, less prone to break easy rotating parts. This Circular Flight Computer does everthing the slide graphic type E6-B do, and you can also use the wind side to solve problem for true wind, true course, wind in flight and speed issues. All printings are sandwich printed between two pieces of plastic so that the numbers/printings never rub off during your long time usage. This Circular Flight Computer help you solve multiple calculations such as flight planning, basic arithmetic or complex in aviation computations. Whether you are solving wind triangle problems, po The calculator side are workable for multiplication, division, and unit conversion and employs scales for performing time, speed, distance, rate, fuel consumption, altitude, airspeed, air temperature, and pressure pattern calculations. grid navigation or pressure pattern flying, it prove its usefulness and versatility constantly. specifications: E6B-R 6 Inch Material: Plastic colour: As shown Package Contents: 1 x aviation plotter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.