6-blades sliding iris mechanism-rack and pinion structure. Parts are designed for laser cutting. It can be used on DIY projects. DXF ,STEPand STL files are included in the attachment. DXF files are for laser cutting, and the thickness is 3 mm. Try to make the kerf as small as possible when laser cutting. You can drive the mechanism by hand or motor. Ignore the OBJ and FBX files, they are only used to meet cgtrader's requirement.What you need to buy are some pins, bolts and nuts.Pin-Diameter 2mm, length 5mm, 60pcs;Bolt,washer &Nut-M3, length 16mm, 3pcs.