Some older cribs contained a "drop gate" (or "drop side"), a side which lowers to ease the process of putting the child into the bed, but can be raised again to restore the integrity of the enclosure. However, assembly problems and malfunctioning hardware on drop gates can cause the formation of gaps, which have been attributed to infant deaths and other major injuries. In June 2011, the United States implemented new safety standards requiring all infant beds manufactured and sold in the country to have fixed sides. In June 2016, Canada implemented a similar ban on the sale, importation, or distribution of any infant bed containing drop sides effective December 29, 2016.