About this 3D model

To fit under the larger housing for the Active cooling fans (http://www.thingiverse.com/thing:304919) I modified this fan nozzle. It works fine, prints great except for the layer at 27.3mm. Not sure why but it just adds a solid layer in and then resumes with the hollow build. If someone wants to look at the model and fix it more than welcome to. I simply just cut out the extra plastic with a knife when it was done printing. Cheers.