by fantom, published
This was a replacement part for a foot pump. The plug was used to lock the foot pump in the closed position.
Design removed and replaced with the flat disk you see, feel free to email for the original if you want it. See following link for details http://traverseda.wordpress.com/2014/05/23/makerbot-blatently-steals-and-patents-a-community-design/
For alternatives to thingiverse see http://www.reddit.com/r/3Dprinting/comments/26do2z/alternative_repositories_to_thingiverse/
I printed it with supports just to make it a little more clean in the overhanging areas. 0.2mm layer height and 20% fill, at about 80mm/s.
The model could do with a little tuning to perhaps better handle the strength in the reducing cylinders, but it's worked well so far.