This is a Czech made reproduction set of German army WW1 M1916 M1917 M1918 helmet rivets (will work for the mentioned helmets either with the steel or leather band. The set has 3 rivets with 2 rivets with a thinner head that go in the front and one with a thicker head that goes in the back of the helmet. The reason the front 2 rivets have a thinner head is so that they will allow the front armor plate to lay flatter on the helmet. This particular type is the one type I tend to se on original helmets. The two prongs are together and then you can open them to hold the rivet fixed thus holding the liner in the helmet.  It is only $4.50 to ship this liner anywhere in the US, Canada, Australia, NZ and most of Asia. Postage within the EU is $4.00. Naturally I do offer the possibility of combining postage to save you money.