Range extension to highly successful 38mm Plasti-Twist and Plasti-Twist Triple Seal caps Amcor White Cap has launched a new diameter for its plastic closures in 33mm size. The 33mm Plasti-Twist cap is a two-piece compression moulded plastic closure, primarily for use in hot fill applications. Produced in a polypropylene material the closure features a compression moulded liner, which is available with or without barrier properties.