Cover interlocking preventive device

Claim 1

A container header comprising: a short, circular, flared skirt having a bottom edge and forming a lateral surface of a container header, a discontinuous ridge means formed on the upper surface of said container header; seven protuberances provided on the lower surface of said header, located at radially spaced intervals of 33*, 70*, 39*, 58*, 51*, 45* and 64* and said protuberances are of a depth such that the protuberances extend to a level above the plane defined by the edge of said flared skirt whereby when said headers are stacked, said protuberances on said lower surface fall upon said discontinuous ridge means on said upper surface to provide a spacing means between headers and prevent interlocking of one header to another, a circular ridge on the upper surface of the header and having formed on its inner side a depression between said first circular ridge and said discontinuous ridge means and having said skirt as its outer side, whereby the inside of said skirt of a first header dovetails with the outside of the skirt of the circular ridge of a second header just below it to prevent the headers from shifting relative to each other when a plurality of headers are stacked upon each other one above the other.