The chest-supported magnifier sets both hands free to handle the observed object. It is suitable for embroidering, knitting, reading, writing etc. The magnification within the outer circle (dia .110mm ) is 2x while the inner circle (dia .20mm ) gives a higher magnification of 4x. To obtain a clear image, adjust the distance between eyes and the magnifier and between the magnifier and the object by lengthening and shortening the hanging cord