Reusable Coffee Cups Think Cups are lovingly made to enhance your drinking experience. The borosilicate glass is durable and can withstand extreme changes in temperature. The food grade silicon lid and band are insulating and lovely to hold. Above all Think Cups help to decrease the damage that we are doing to our environment by throwing away billions of disposable cups every year. Think Cup is an Australian company based in Sydney and we are very proud to be wholly Australian owned.