See the source model for usage instructions. The largest of the three pictured is the original size.

I made these smaller flexible passthroughs thinner to be more flexible but did leave a full height ring to screw onto.

I reccomend a layer height of 0.2mm for printing  the flexible passthroughs since the flap thicknesses are .6mm and .8mm.

A smaller layer height for better detail in the threads would probably be better. I used 0.16mm.

No supports are required.