Cob rollers are cylindrical tools used to roll and flatten cob, a traditional building material made from a mixture of soil, clay, and straw. Synonyms for the term "cob rollers" include cob pressers, cob tamperers, cob flatteners, cob shapers, and cob formers. Each of these terms represents a specialized tool used for a specific task in creating cob walls or structures. Cob pressers are used to compact the cob mixture, while cob tamperers and flatteners are used to smooth and level the surface of the cob. Cob formers are tools used to mold and shape the cob mixture into specific shapes or sizes.