Easy to use,their unique built-in funnel design enables you to easily fill the water without using an extra funnel.This whiskey ice ball maker is made of durable premium silicone material, totally healthy to use without leaving any after taste,as the non-stick feature of the silicone,simply push on the bottom,the ice balls will pop out easily.Large size ice ball melts slower than the conventional ice cubes,keeps drinks colder,longer,and with less dilution.Perfect to chill your whiskey,cocktails,scotch,rum,tequila,vodka,vourbon,mixed and non-alcoholic drinks.