5000ml Erlenmeyer flask great for those larger yeast starters for 10 gallon plus batches of beer.
Made of borosilicate glass (Pyrex)you can move it from boil to a cold water bath. Making your yeast starter in one container saves you time and saves your yeast from contamination
It is recommended to use a double boiler method to heat your flask. Use your brew kettle filled with water to boil in.