Child-resistant (CRC) closures, are often called as child-resistant caps or safety caps, and are used to reduce the risk of a child poisining by consuming hazardous materials or chemicals. This is 28-400 white ribbed push and turn cap features a F217 plain liner, which is a general-purpose foam liner. Child resistant closures are often used on prescription drugs, over-the-counter medications, nicotine products, pesticides, household and industrial chemicals. Note: F217 liner is taste and odor resistant, and has a low moisture transmission rate, meaning it prevents moisture from entering the bottle and affecting product.