Health and hygiene. Made of food grade stainless steel are filled with frozen liquid, are more durable than regular ice, and are less likely to produce bacteria and are more sanitary. Odorless and non-porous, will not dilute drinks, also will not affect the flavor of the drink. It's easy to use, as long as you keep the rocks in the freezer for 4-5 hours, the gel in the ice will solidify. Can be used for Irish Whiskey, Scotch Whisky, Japanese Whisky, Tennessee Whiskey, Rye or Bourbon, liqueurs, white wine, coffee, juice, even all kinds of drinking.
