About the size of a credit card, these magnifiers have a lens that slides out of the case to inspect items and equipment on the go. When you slide them open, a bright, even LED light automatically turns on to make it easier to see details. The light will last twice as long as other LEDs. Unlike traditional magnifying glasses, the lens on these magnifying glasses is made with a curvature that corrects for distortion near the edge, giving you a crisp, clear view across the entire lens. This is helpful when checking the shape and size of an item. The lens is glass, so it's clearer and more durable than a plastic lens. The case functions as a handle when in use.