Freeze Glass FICE01051 9.8-Ounce Ice Bowl The freeze glass will keep a drink cold for up to 30 minutes Once frozen, the glass will chill your drink within 2 - 3 minutes to a temperature between 0DegreeC and -2DegreeC (32DegreeF and 36DegreeF) A freeze glass can be activated by keeping it in the freezer Amsterdam Glass is the patent holder of the special consumer safe and environmentally friendly glass cooling technology Freeze Glasses are dishwasher safe and approved