The M4A1-S Silver features a silver texture in its body and it comes with a silencer equipped to it which greatly reduces the noise it makes. This comes with a magazine which carries an extra 5 bullets. That brings the total ammo capacity 35/105.
There are other Cross Fire papercrafts at the site:
Cross Fire – Desert Eagle Gold Free Pistol Paper Model
Cross Fire – Desert Eagle Green Vein Free Paper Model
Cross Fire – Combat Axe Autumn Camo/Octane Free Paper Model
Cross Fire - SCAR Light Assault Rifle Free Paper Model Download
You can download the papercraft model here: Cross Fire - M4A1-S Silver Assault Rifle Free Paper Model Download