Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Broken glass

The description says they are borosilicate glass which is strong. Today after making a shot I put the glasses (like I always do) in a tub of water in the sink. When I later went to wash them one was broken, the outer shell had broken off. It feels like plastic. I never dropped them and never use too hot water.Not impressed as i have used them only this year maybe ~100 times.Bodum's web site say they do not warranty glass but i emailed them anyway.I did email and they replaced them at no cost. Thx!