The lid/cap on the German flask model 1931 (and the like) aluminum.
Gorgeous copy, which is difficult to distinguish from the original, especially if stamped. The lid is without stamps. The lid is completed with a rubber gasket. The peg is not installed in the lid, but attached to it. It needs to be riveted after installing the cap on the flask strap.
Price per set: cover + red rubber gasket + peg (rivet).