Thank you for viewing. This is a gua sha from Alqvimia, a Spanish natural cosmetics brand. The four different straight and curved lines fit perfectly into the angles of the face, allowing for a smoother massage. Purchasing from their website costs £45 (approximately 7300 yen) plus even higher international shipping fees, so please consider this if you are interested. Also, you can search "alqvimia gua-sha" on YouTube to find tutorial videos using this gua sha. There are holes and cracks in the stone, which are characteristic of Bian stone. These are inherent to the product and present from the beginning, but please refrain from purchasing if you are sensitive to this or seek perfection. (Please refer to the last photo.) Thank you.