This star wars papercraft is a Stormtrooper Helmet, created using 2 mm thick EVA (Ethylene-Vinyl-Acetate) foam. This star wars paper model is designed by Julius Perdana from paper-replika. The distinctive helmet has a similar shape as the German Stahlhelm (also used during the latter half of World War I). The waist gear in some ways represents the ammunition pouches of German soldiers. Another similarity is the small cylindrical shaped case resting on the lower back of the wearer. The German gas mask cannisters of World War II had the same cylindrical shape and also rested on the lower back.
This pep file scale is set to 1 (1:1 scale), the complete helmet is 27 cm / 10.6 inches in height, if you want make it bigger change the scale with 1.1 if you want to have 110% size or 1.05 for 105%.
You can download this cool helmet paper model from here: Star Wars - Life Size Stormtrooper Helmet Free Papercraft Download