This Push-Fit Check Valve is a one way check valve/non-return valve for 10mm OD kegging lines.
Note that this is 10mm diameter in and out - if you're after 8mm, you'll find it here
They are extremely easy to use and allow you to simply push your beer and gas line straight into these fittings. No need to purchase clamps or tools. To remove the fitting, simply push in the collet and the hose can be removed. Fits 10mm outer diameter tube.
Note: colour may vary.