Portability: Small, fits in a coat or hip pocket.
Contents: Primarily hard liquors; not ideal for beer, wine, or fizzy drinks, but water or non-fizzy drinks work.
Materials: Common materials include stainless steel, pewter, and leather-wrapped finishes.
Gifting: Popular gifts, often personalized with engravings, and sometimes sold in sets with funnels or shot glasses.
Care: Recommended to clean regularly, especially stainless steel ones, to prevent off-flavors.