Why do the Halo 4 chest pepakura armor only on the front?

[indianastanley]

i got confused.
I need the whole armor chestpiece for halo 4 recon, and it is not full, only the front. why is that?

 

[Raquisite]

http://www.405th.com/file-archive.php?do=download&downloadid=777

Seems fine to me.