KL-1 Russian

Technical Features
Manufacturer: Russian Year: c1968 
Info: 50 millimeters in diameter, The KL-1 is intended for performing trigonometric and mathematical operations: Multiplication / Division / Squaring / Extraction of a square root / Finding of trigonometric functions of a sine / Finding of trigonometric functions of a tangent / Finding inverse trigonometric functions /  Calculation of the area of a circle. Donated by my friend Bohdan ( Богдан Ukraine )