Abstract: A closure is provided for a container having an externally threaded neck and a plurality of locking teeth. The closure has a first outer side wall, a second inner side wall, and projections within the outer side wall for engaging the locking teeth of the container, to prevent removal by children and the like. The outer side wall can be distorted to displace the locking projections, for opening the container. For forming a seal with the neck of a container, one or both of a textured finish on an annular sealing surface within the second inner side wall, and an internal sealing lip are provided. This eliminates the requirement for a separate sealing liner.