This is a reproduction of a German WWII early type canteen screw cap with a gasket and rivet. The cap is made of a hard plastic resin that that simulates the original Bakelite very well. The gasket is food grade rubber type material and the rivets is aluminum. Many canteens have the cap either damaged or missing so here is your chance to replace it. To install the cap you have to tap the end inside the cap so as to widen the rivet bottom so that it forces the tip wider and holds on the inside of the rivet hole on the cap. You may need a flat bottom punch to accomplish this task.  It is  $5.00 to ship this item anywhere in the US, Canada, Australia, NZ and most of Asia. Postage within Europe is $4.50.