Buttons of brown color, diameter of 13 mm from synthetic polymer. Such buttons served as a distinctive feature of the Jäger caps in the initial period of the war. Later, all the buttons were metal.
Read about the history of this item and its use on the tab "Historical reference".
A rare thing! You need usually 2 buttons for a cap. Price is for 1 button.
Buttons on Jäger caps. Left: a Jäger in the tropical jacket made of Italian fabric "Olona". Photos from facebook.com.
Right: a Jäger in an M41 jacket with isignia set installed according to the 1935 rules to have the "veteran" look. Photos from forum.ww2.ru
The original buttons were made from Corozo nut, the fruit of a palm tree that grows in South America. It is also called vegetable ivory. Prior to the wide distribution of plastics (which the Germans themselves, by the way, were actively developing before and during the Second World war); horns, bones, wood and nuts (cores or shells) traditionally served as button material. Therefore, for the beginning of the XX century, nut buttons were not uncommon.
However, nowdays it is not so easy to find or manufacture walnut buttons. The main material of the beginning of the XXI century is plastic.
Corozo nut and buttons made of it. Picture from best-guide.ru