The hole size is approximately 1.6mm. Please connect the parts using rings. It's very light, so it's also recommended for bulky accessories. It has a natural stone-like color and a marble pattern. *Due to the manufacturing process, there may be individual differences in the degree of marble patterning depending on the item. *Due to the manufacturing process, you may occasionally see a white part (residue of abrasive), but it can be easily removed with your fingernail. Also, if there are any clogged holes, you can easily remove them by punching. *Depending on the item, there may be white marks on the top. Please note.