DESC: While allowing pressure to build only when the covers properly closed the airventcoverlock prevents the cover from opening until pressure is safely reduced, Presto pressure canners double as water bath canners for preserving fruits jams jellies pickles and salsas; constructed of extrastrong warpresistant aluminum, Includes a cookingcanning rack along with a book of instructions and recipes, Hand wash; UL listed, 12Hx15" dia.