This item was created out of a perceived need for Mercari users. We are confident you will be satisfied with this product. This is a tool to check if items can be mailed via Yu-Packet Post, made from cedar wood. It has slits of 4cm and 1cm. The material is cedar. The refreshing aroma characteristic of cedar has a relaxing effect, as well as antibacterial and insect-repellent properties. Wood is flexible and strong, becoming smoother with use, and is kind to nature. And the texture of the wood is superb. It is unpainted. The material is cedar wood approximately 14-18mm thick. It does not bend flimsily like a thin ruler. It is sturdy, just like an actual mail slot. You can check in advance whether your package can be crushed and inserted. We believe there are no commercially available measurement tools with this thickness. The photos are for size and shape reference. The item you receive will be of equivalent quality. If you would like measurement slits of different thicknesses (e.g., 1cm or 5cm), please contact us via the comments section on our custom order page. It may take some time, but we will do our best to accommodate your requests. We will use recycled materials for packaging. If you purchase multiple items and they can be shipped together, we will reduce the price by at least the shipping cost. We may change between Yu-Yu Mercari便 and Raku-Raku Mercari便 without prior notice. Thank you for your understanding. #Takatowoodhandmade #Takatopackingscale #YuPacketPost4cm #YuPacketPost #ThicknessMeasuringRuler #ThicknessGauge #ThicknessMeasuringTool #ThicknessMeasuringGoods Yu-Packet Post Thickness Gauge 4cm