Iris mechanism designed for 3d print. There are 5 leaves. Then you rotate the Drive Partor the middle plate, the center hole can open or close gradually. The center hole is diameter 30mm, the outer size is diameter 70mm and thickness is 8.2mm. To assemble the parts togther,some M2 screws are needed.It is best to use resin material when 3d printing. And you may need to sand some parts due to the 3d printing quality.Ignore OBJ and FBX format files, they are only used for cgtrader's requirement.