A smaller Instrument specifically designed for the Yachtsman where space, weight and size are at a premium, features include: The comfortable light metal alloy frame is well balanced. The large horizon and index mirrors are tested for optical flatness and parallelism. The front focusing telescope 2,4 x 25 is ideal as the rubber eyepiece does not turn against the rim of the navigators eye during adjustment. To prevent eye damages, the correct amount of brightness through the sextants optical light paths is controlled by means of swing in graded filters, 3 for the index and 2 for the horizon mirrors. Option: Illumination device which is detachable (battery operated).