The HEV suit is a power suit worn by Gordon Freeman in Half Life and Half Life 2.
More Info: http://half-life.wikia.com/wiki/HEV_Suit
Skin: You can find the skin I used for the helmet here http://www.planetminecraft.com/skin/hev-suit-mk-iv-v2/
Scaling: To make the helmet fit on a character, before printing resize it to 120%.
Note: I probably should have uploaded this with the Gordon Freeman Papercraft...
1. Click on the papercraft design image.
2. Make sure it has not been resized by your browser (you might need to click the image again).
3. Print using your browser's Print function.