Duralex Stacking tumblers are practical and durable, made from Fully Toughened glass and also come complete with a stacking lug. Fully Toughened glassware has been strengthened across its entire body making the glass resistant to impact damage at all points. When Toughened glass does break, it will break into small fragments making it impossible to cause serious lacerations. This makes the range an obvious choice for outlets following license stipulations or those seeking to prevent glass related violence.