The gun takes a standard 8.4 volt stick type battery. The battery compartment is the standard folding stock type, accessed by removing the dust cover. It uses a standard car fuse, like other VFC models.
Muzzle brake is screwed on and then held in place by a spring loaded pin.
Size comparison with M4
Now onto the blow-back feature. It's with out a doubt a neat feature. I did however noticed that in semi the bolt would bind up and I would have to take pressure off the return spring and fire a round to get it to cycle again. I have not attempted to take apart the gearbox and really figure out how it works. In the attached video you will see how the bolt is run off the gearbox. You'll notice that when the piston does not make a full revolution the bolt does not return to battery. The 2 page instruction insert says that if you attempt to use a 9.6 or higher the bolt will automatically disconnect. Don't know if I believe that. Excuse the large battery and the jury rig, I did not have a stick charged.
As far as how does it shoot. That will have to wait till this weekend for a true test. I'll update the review after I get some time with the gun.