I bought this as a spare for repairs at MASH.CO in Osaka, but I no longer need it, so I'm putting it up for sale. The following is the manufacturer's description. For those who love and collect military clothing, replacing missing buttons is a headache. Finding buttons with a similar shape and color to those used on clothing issued in the 40s-60s is extremely difficult, and many people have had to settle for something that doesn't quite match. MASH has now started selling reproduced buttons that faithfully reproduce the material, shape, and color of buttons used on various military clothing from the past to the present. Please use them for repairing your military clothing. ■ Main Use: US NAVY P-Coat ■ Shape: A distinctive flat button with four holes and an anchor engraved on the surface. *See image ■ Color: Black Note: Please be aware that there may be slight color variations between manufacturing lots, and color differences may occur depending on the viewing environment. ■ Diameter: 31.4mm ■ Thickness: 5.5mm ■ Material: Urea resin (urea resin) A synthetic resin made from urea and formaldehyde aqueous solution, developed in Germany in 1920. It was first used by the US military in the 1930s because it was relatively easy to mold and suitable for mass production, and it continues to be used today. The simple texture of urea resin buttons, which are different from the petroleum-based synthetic resin (often called plastic) buttons widely used in the civilian sector, is a perfect match for military clothing. ■ Supplement: Even among buttons used on military clothing of the same type, there are many variations in shape and color. The product offered here is a reproduction of what is considered to be a representative one among the many variations. In most cases, there will be subtle differences when used to replace a missing button. It might be a good idea to remove and store the remaining original buttons and replace them all with the reproduced buttons.