HK I think it is about time that you tell us what these are used for. A lot of us have tried to figure it out but it seems none are right. Surely if you buy a product from the supplier HK - then why did you bought it in the first place if you cannot tell the application. And why are you not asking the manufacturer what they should be used for. As it is now, they have been in stock for maybe one year and I bet you not many have been sold. That is very ***r business in my book.
I think F100cufflink reply is correct but still, what is the size?D10xd4.5xL1.26mm?? What is 1.26 mm long? And what is D10 mm? It's a pity one has to spend almost 8 bucks to find out. I am too greedy for that. And there is no review so I think this item is a lemon for HK with none sold.