Up To 23 Magnifications: Exclusively designed with 2 lens slots and 1 fixed front round lens(8X), the two back lens slots can be loaded with single one or two lenses at a time from the five(1X, 1.5X, 2X, 2.5X, 3Xand 3.5X). Simply install 3 AA batteries (Not Included) and take it anywhere. Foldable Lens Allows Free Combination: All lens on the headlamp can be folded when not needed, therefore you can use any single lens or any free combination from the three ( 1 fixed lens and 2 replaceable lens on the dual slots ). 3 lenses combined to get high up to 23 kinds of magnification: 1x, 1. 5x, 2x, 2. 5x, 3x, 3. 5x, 4x, 4. 5x, 5x, 5. 5x, 6x, 8x, 9x, 9. 5x, 10x, 10. 5x, 11. 5x, 11x, 12. 5x, 12x, 13x, 13. 5x, 14x. Wear Comfort: Soft breathable sponge padded headband with two rotary knobs on the left and right, rotate anticlockwise to release the whole lighting frame from the headband so that you can freely regulate the total lighting frame upwards or downwards to the angle that is needed. Tail knob used to adjust headband size for fit over different head, pull it outwards and rotate left or right to get your head size, then press it to lock. More Precise Lighting Angle: Besides the adjustment of the whole lighting frame mentioned above, the lighting unit equipped also has 45 degree rotation up and down when landed on the whole lighting frame, plus the 3 LED lighting part on the lighting unit can be slightly pointed left and right with fingers for more precise illuminating angle. The lighting unit can be taken down as an independent handheld flashlight for daily or outdoor exploring. How Much It Helps: Magnifier working lamp, with scores of magnifications available helps improve your low vision and provide you clear viewing even while sewing. Made to be headband style, its totally handsfree. Ideal for reading, painting, observing, modelling, repairing, sewing, soldering, jewelry making and other hobbies/ crafts.