E6B includes calculating time, speed, distance, altitude, true air velocity and density altitude questions. Great for flight training. On the front of the flight computer is a logarithmic sliding rule that performs multiplication and division. The wheels on the back of the calculator are used to calculate the effect of wind on cruise flight. Lighter, smaller, less breakable, one-handed, faster, and requires no power. E6B flight computer is the preferred manual computers of instructors and students alike! Due to different production batches, the color and packaging will be slightly different, but the products are of high quality. Material: plastic colour: As shown Package Contents: 2 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.