This spectacle with flip-up metal frame and clip-on sunglass was developed from our engineer and patented item here in Korea.
This can be used a reading eyeglass with sunglass at one time because you can use nomal eyeglass usually and when you need sunglass then you can attach a sunglass lens on frame and this can be flip up during in use and can be detached away from spectacle frame when you do not use anymore.
In other words,you want to use as sunglass then you can attach a sperated sunglass[...]