Wanhao Duplicator i3 Filament Guide Tube Adapter 4mm

Based on this (obviously, Drazen gets all the credit) http://www.thingiverse.com/thing:877258. But the 4mm version didn't import into slicer (0 size). I went ahead and just scaled the hole by 0.667, which is enough to fit the 4mm OD tubing snugly.