Print with flat surface on print-bed, as shown in picture with vent installed. 

Got a spare vent-plug to avoid disaster, but no easy way to remember to carry it with you? Print this and never be caught unprepared! Vent-plug threads into base, with o-rings protected without being compressed. 

To be used with the Blue Robotics Vent Plug for water-tight enclosures. 

Feel free to remix - CAD available in onshape: https://cad.onshape.com/documents/78f1978d486f0cc6135ff626/w/e2bfade55a7e617d9b7fa4aa/e/665d456718faf6e504991485?renderMode=0&uiState=6596f3904828083e94be9a42