Your concerns are here Q:Is glass fragile? A:Glass is a fragile item, in the process of use, please take care to avoid external bumps or fall to the ground, does not guarantee that the fall will not break. Q:Why is there a small protrusion or other small defects on the cup? A: This product are manually blown, blowing process bubbles and other small defects are normal phenomenon, but also the difference between handmade and mechanical processing.