BonJour Coffee Insulated Borosilicate Glass Espresso Cups, 2-Piece Set, 6-Ounces Each The espresso cups' distinctive hand-blown borosilicate glass design is both beautiful and durable These 6-ounce insulated demitasse-sized cups are crafted with two layers of glass to help keep beverages hot Innovative double-wall design provides an elegant visual effect; the insulated glass construction also helps prevent heat and condensation rings The eye-catching glass cup set makes a thoughtful gift for beverage connoisseurs and partners well with other bonjour coffee and serve ware items Quality assurance guarantee