Double walled polycarbonate outside w/glass inner travel mug infuser tumbler Here are 2 ways to make tea in LibreTea Tumbler: #1 – for leaf teas/fruits that can be re infused or do not go bitter: — remove lid & filter add tea into glass carefully pour hot water into glass allow steam to clear, 1 – 2 minutes twist on filter & lid… you’re ready to go! — #2 – for teas with limited steeping times remove lid & filter carefully pour hot water into glass allow steam to clear, 1 – 2 minutes twist on filter only place 1-2 tsp of tea on filter screen twist on lid carefully turn your libre upside down, steep to desired colour/flavour turn upright… ready to go! STEAM WARNING – Always Remember… Trapped steam builds up pressure. Allow steam to dissipate before tightening the lid. Use care when removing the lid on hot teas.