These cups are made with bamboo fibre, cornstarch and resin, making them naturally sterile, with no plastic after-taste. the re-sealable "no-drip" lid along with the sleeve are comprised of a high grade, latex-free silicone. they are bpa, bps and phthalate-free. you can pop it right in the dishwasher but it is not suitable for the microwave. available in so many sizes and styles, pick your favorite: 8 oz - superhero, william morris: walthamstow 12 oz - inca, kerr & napier, leave it out arthur, threadneedle, look into my eyes, farfalle, papafranco, toolondo fisherman 14 oz - william morris: poppy, willow, lily, acanthus, milperra mutha, marmo verde, kai leho 16 oz - kerr & napier, mrs mills, nathan road, grand rex, yo' twitches