
Continuity mistake: Just before Michael says "You're going to pull the bullet out with your bare hands?", Sawyer's hair is very wet and pulled back, as if it were in a pony tail. When the camera switches back to Sawyer saying "You got a better idea?" his hair is a lot drier and covering his face. In the next shot, it is pulled back again. (00:15:10)
Chosen answer: If you watch the Animatrix it explains the whole plot, half of the machinery was constructed in Zion, while all the hovercraft's are what remains from the day before the war, and the APUs look like they have been constructed in Zion and used for construction, the guns and ammo packs are mountable.
Kirill Ostapenko