What is a vitrified coffee mug?

Vitrified coffee mugs have undergone a special firing process that makes them more durable, more resistant to chipping, and less likely to absorb water. Only Custom Vitrified Mugs can withstand commercial dishwashers and are thus suitable for restaurant and food service use. Use the Durability filter to view only vitrified mugs. The screenshot below shows where to find the Durability filter on Deluxe.

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