Stellbrook Klarvid Double-Wall Glass Cups (Set of 2)

A pair of 250 ml double-wall cups in borosilicate glass — the low-expansion glass used in labware, so boiling water straight in is fine and thermal shock is not a worry. The sealed air gap between the walls does two useful things: it insulates, keeping coffee hot longer while the outside stays cool enough to hold without a handle, and it makes the drink appear to float, which never quite stops being pleasant. The size suits a single pour-over, a cortado-scale milk drink, or espresso with room. Because the walls are thin glass rather than ceramic, preheating matters less; the air gap does the work. Dishwasher-safe on the top rack. Sold as a pair because one always ends up claimed by someone else in the house.