Mouth-blown by master glassblowers, tumblers with exceptionally heavy bases, and fine walls. Distinctively heavy bases and fine walls highlight the quality of these mouth-blown glasses. Fine walls and weighty bases accentuate the clean lines of these modern tumblers. Expert craftsmanship is required to make and finish each piece by hand. The Boris tumbler is mouth-blown by master glassblowers to create the signature thick base. The fine rim is fire polished to create a smooth finish.