Clean sealant injection: this oversize syringe (100ml capacity) injects the special Caffelatex sealant through the valve, to seal the fitted tire in a clean way.
For Presta valves only (removing or not the valve-core), with a long tube for easier application.
This injector is a big help with the sometimes messy job of adding Stan's or other tire sealant liquids to your tire. i can be used directly through the stem, but I find myself even using it to put the liquid in through a small gap in the sidewall when I am mounting a new tire. Works great either way.