This Duotight 8mm plug is good for testing for gas leaks and plugging up unused connections in tees or other fittings.
About Duotight Fittings - Duotight fittings are very high-quality, high-performance push-in fittings that use a double EPDM seal to ensure a solid, leak-free connection under a variety of situations. This makes it very easy to swap fittings and lines without clamps or fear of leaks.
To ensure a leak-proof seal, please cut tubing as squarely as possible, using a razor or very sharp knife. We recommend the Tube Cutter w/ Duotight Removal Tool for this.