This turret can fit one droid minifig, but cannot be used with a regular minifig, unless put into an awkward position.
About this creation
This turret can spin because of the round rotating black piece on the bottom. I have to give credit to a youtuber, who posted a video called "LEGOŽ Star Wars stuff" and I modified his/her design. If you watch the video it may appear I used the same exact parts, but I used many different bricks right above the swiveling piece.