Child-resistant molded plastic container lid for open head containers

In combination;

• a child-resistant molded plastic container lid and an open head container, said lid having an annular inverted U-shaped rim containing threaded portions and configured to fit over and receive the upper peripheral edge of said container, said container having threaded portions about its outer upper periphery for mating with said threaded portions of said lid, the improvement comprising,
• locking teeth provided on the inner peripheral surface of the upper end portion of the container, and
• resiliently biased locking means mounted on said lid engaging said teeth when said lid is threaded down upon said container to a closed position, to thereby prevent rotation of the lid in the opposite direction to an open position by a child, whereby the container and lid are child-resistant when closed.