38mm 38-400 White PP Plastic Child Resistant Vented Cap, 3-Ply Foam Liner

The 38 mm 38-400 white PP plastic child resistant vented cap with foam liner is a high-performance closure designed to protect product integrity while safely managing internal pressure. Engineered with a 3-ply vented foam liner (YC4 / Circumvent™-style technology), this cap allows containers to “breathe” by equalizing pressure both before and after opening—helping maintain container shape and preventing paneling or bloating during storage and distribution.

This vented closure is ideal for products that naturally release gases or are sensitive to pressure changes, such as oxygen-scavenging formulations, chemicals, cleaners, agricultural products, and specialty industrial liquids. The liner remains inside the cap throughout the life of the package, continuously regulating airflow while maintaining a secure, leak-resistant seal.

For added safety and compliance, this cap features child resistant functionality with embossed pictorial open/close instructions, making it easy for adults to use while helping restrict access by children. The B-vent membrane design delivers reliable venting performance without sacrificing package security or value.

Unlike traditional vented closures, the YC4 liner design allows gas to escape through grooves on the back of the liner and the cap threads.

This 38 mm child resistant vented cap is sold separately from containers, offering flexible compatibility with a wide range of 38-400 bottles.

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