Durability + Care Our coupe glass is made from borosilicate glass. Borosilicate glass is completely non-toxic and contains boron trioxide which allows for a very low thermal expansion. Meaning our glassware will not crack under extreme temperatures like regular glass, making our glassware dishwasher safe and safe for all your coffees, matchas, chais, cocktails and more. Handcrafted Each glass is hand blown and handcrafted. Glass is handblown into our custom moulds, while continuously rotating to distribute the glass evenly with the perfect composure of glass and air. Then each glass is placed to properly cool. Sizing 4.5" w x 5" h 8 oz