samaDOYO S017 Tea Cup with Glass Strainer, Stainless Steel Lid and Silicon Protection Glass 370ml 370ml green They are made from borosilicate glass that transparency is as high as 92.8% (diamond transparency 93%) Silicone sleeve provides insulation to cup and protects hands when drinking Instantaneous temperature can range up to -30-150 Capacity: 370 ml Removable tea filter made from borosilicate glass