The Lastu Teacup is made of UPM Formi EcoAce wood biocomposite that come from almost 100% renewable sources with 87% lower carbon footprint than plastics. Material is from Finnish wood industry sidestreams – so no trees need to be harvested for it. Wood from only sustainably managed forests. The angular base and single sided infuser let you adjust the taste of your tea by tipping the Lastu Teacup from side to side. Dishwasher safe. Each Lastu teacup has unique rough surface pattern.