This product is a seal-engraving tool called an "intou." It's a stand used to hold and secure the seal material (stone for the seal). It is used for "fuji" (writing the characters) and carving the seal. By firmly securing the seal material, it prevents injuries and allows for bold "untou" (the way of using the engraving knife). The one in the photo is made of wood and features a screw-type fastener.