Alto’s white* 38/400 thread caps (wad-seal version) with Super Resistant Vent (SRV) grooved back foam liner (Circumvent YC4 grooved back foam liner F-217-30 WC). Gas escapes out, or comes in, via the grooves in the liner and the cap thread, so no hole is required.
We can insert this vent into 38mm caps for customers, as long as the cap is a wad-seal version as we can not fit a liner to a cone seal cap.
Vented liners made by Selig Group, USA
*We currently do not stock these in black but they can be sourced.
Also See:
600819 28/400 CRC with grooved back vented liner
600830 38/400 CRC with C4CR foam vented liner
Venting of caps allows containers to ‘breathe’ which stops them blowing out or sucking in. Some products emit gas, which must be allowed to escape or the container will start to bloat and could crack or explode and they are unstable on the shelf. Other products are oxygen scavengers so they cause the sides of the container to suck in (panel) which causes labels to fall off and instability.
For our venting guidelines please click here: Venting guide 2026 and call us if you have any questions or require samples for testing.
Vented closures must be tested under your specific end use conditions at your own discretion and risk. This is the recommended testing process but we will advise you for your specific vents if it differs 3SL Vent Testing Process 2024
