Description The Husk BreakTime Tumblers are heater and freezer safe, as well as Microwave safe (up to 3 minutes). Made under 1.96 Mpa pressure (equivalent to 200 tons). It is 1.27 times harder than glass and the high density with no pores prevents bacteria build up.Because it\'s made from pure Husk it also contains no Formaldehyde or metallic substances.Packed in a set of 6 . Specification Dimensions: 8.5cm Diameter x 7cm Tall Temp. Range: -30 to 120 Degrees Celsius  What is Husk? All OLPRO Husk Tableware is made from rice husk (the little shell rice comes in!). They are eco-friendly, biodegradable and does not contain any harmful substances at all.Rice husk is an agricultural waste. Annually, the world\'s rice production is approximately 500 million tons. Of this, the ratio of rice husk to rice is approximately 1:4, which is equivalent to about 125 million tons of rice husks produced each year.   .