All of Ollie & Grace tumblers are hand made with epoxy and Oracal 651 permanent vinyl. Tumblers should be hand washed with mild dish detergent and air dried to prevent epoxy from softening or vinyl from lifting. Do not place in dish washer or microwave. Do not leave in a hot vehicle. Do not drop. Ollie & Grace is not responsible for cracking of epoxy, melting or softening of epoxy, lifting of vinyl or vinyl falling off due to mishandling and washing in the dishwasher.