Yamada Kogyo wok is made by a hammer (machine) for thousands of times using a "hammer" method. [Hammering] is a manufacturing method that allows the pot to be turned by hand and using a special machine with a hammer after pressing a single flat sheet of steel sheet and then rearrange the pot shape by hand. Because each product is handmade by a hammered method, each product has fine scratches, welding marks, and scuffs. Due to the production process, the surface of the product may appear like scratches at first. In addition, due to high heat treatment when welding the handle parts, color difference and black leather peeling may occur, but this does not affect the quality of the product, so please rest assured that you can use it.