oushiun usb rechargeable led reading glasses smart lighted eyewear for women men (black, 1.5x) oushiun specification<br><br> lens height:41mm/ 1.61" (approx.) <br><br> lens width :50mm/1.96" (approx.) <br><br> leg length :145mm/ 5.70" (approx.) <br><br> bridge :17mm/ 0.55" (approx.) <br><br> weight:39g<br><br> instruction table: <br><br> the following table shows how the power of lens changes with age, and it's for reference only. <br><br> 45 - 49 years old: +1.00 <br><br> 50 - 54 years old: +1.50 <br><br> 55 - 59 years old: +2.00 <br><br> 60 - 64 years old: +2.50 <br><br> 65 - 69 years old: +3.00 <br><br> 70 - 74 years old: +3.50 <br><br> 75+ years old: +4.00