Thinset (also called thinset mortar, thinset cement, dryset mortar, or drybond mortar) is an adhesive mortar made of cement, fine sand and a water retaining agent such as an alkyl derivative of cellulose. It is usually used to attach tile or stone to surfaces such as cement or concrete. It is particularly popular among mosaicists for outdoor applications
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Thinset Wikipedia(Text) CC BY-SA