What's an Arm Cannon??

TaDa!!!! I'm done with this... and now, I'm going to go and finish that blasted piano model!!! The next thing I'm putting up here on DA shall be a few renders of that piano! And you will all love it, lol.

Anyway, I did this when I was wondering about the armcannons they both have and if they could do their jobs if they didn't know what they were. .... or something... Anyway, let me know what you think!