Thingiverse

Sodastream Carbonator Cap by theron
by Thingiverse
Last crawled date: 4 years ago
Sodastream makes home drink carbonators and they use metal takes for the CO2, which come with green plastic caps to protect the threads (which are mostly but not quite exactly standard CO2 fittings). The caps are easily lost or broken, and the are a generally awful green color (not unlike Thingiverse's STL renderer's default color).