Please check image 4 for the approximate age of the item. It started working when exposed to sunlight. I looked at the manual and tried to adjust the date, etc. The wrist size is about 19cm, so it's a large size. It appears to be for women, but the color is matte, so it seems like men could wear it too... It's working without any problems, but it's an old item and I can't take responsibility for it. I don't know how to remove the clasp properly and I'm afraid of breaking it, so I haven't tried it on my wrist (^◇^;) Considering all of the above, it's being sold as a junk item. To prevent any trouble, please consider purchasing it only if you understand and agree with the condition.