Key Features and UseDesign: These sets often include "bent" or curved designs to make drinking more comfortable.Material: Usually made from food-grade stainless steel (such as type 304), they are durable, rust-proof, and BPA-free.Versatility: They can be used for a variety of beverages, including smoothies, milkshakes, iced coffee, and cocktails.Cleaning: Most are dishwasher safe, but it is highly recommended to use the included brush with warm soapy water to scrub the interior thoroughly.