Caterer's vessels refers to URNS, which are large metal or ceramic containers used to store and transport hot beverages such as coffee, tea, and hot chocolate. They are commonly used by caterers for events such as weddings, parties, and other gatherings. URNS are typically made of stainless steel, aluminum, or ceramic and come in a variety of sizes and shapes. They are designed to keep beverages hot for extended periods of time and are often decorated with intricate designs.