Designed with functionality in mind, these tumblers are stable, guaranteed unbreakable for 10 years with normal use, dishwasher safe, and stain and scratch-resistant. Australian-made and owned, this sustainable glassware is made from BPA-free Tritan and is 100% recyclable. Care Instructions Modern dishwashers with their low-velocity jets and moderate temperatures of around 75 degrees C are the best way to retain the original surface sparkle and clarity. If washing by hand, avoid using a scourer or nylon brush as this may scratch the surface. Light buffing with a lens cleaning cloth will remove some small scratches. Avoid using some aniseed-based drinks such as Ouzo, Pastis, Ricard and Pernod as they may cause permanent damage. Avoid using strong solvents as they may cause permanent damage. Use organic solvents to remove stains, coffee build-up and label glue. Avoid touching the glasses if sunscreen is on your fingers as marks can be baked into the glass during dishwashing. Remove marks prior to dishwashing with detergent.