Head Wearing Magnifier, Folding Magnifier Head Mount Magnifier With Phone Stand Headband Storage Box For Mobile Phone For Reading 270-450mm Focal Length

Head mount magnifier composed of eyepiece and objective lens. The eyepiece is closer to the eye, and the objective lens is in front of the eyepiece. Adjustment wheels can be used to change the magnification of the magnifying glass by moving the objective lens forward or backward