The 50, 100, 250 and 500 ml sizes could be used for stepping up from a slant or bottle dregs or for storing yeast slurry. The 1,000 ml could be used for a traditional starter.
These are made from Borosilicate glass. This type of glass can be moved directly from heat to cold. I regularly go from my (gas) stove top to an ice bath with my Borosilicate flasks.
213B2 Karter Scientific Glass Erlenmeyer Flask 5 Piece Set 50, 150, 250, 500, & 1000ml - $19.99 + Free Shipping with $25 order.
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