Erlenmeyer flasks are commonly used for simple measuring, storing and mixing of liquids. These flasks can be placed over direct heat to heat up solutions. Features: Heavy borosilicate glass design produces a uniform glass thickness Heavy beaded top rim for safety Large, white capacity scale with 50 mL graduated intervals and a 25 mL subdivisions Durable matte finish marking area for use with an ordinary pencil Erlenmeyer flasks can be used as a wine or juice container or culture chamber. Since borosilicate glass can be autoclaved to render it sterile, they are used as fermentation vessels by home brewers or microbiologists. An Erlenmeyer flask has similar accuracy to beakers but less than graduated cylinders. Choose from single pack or pack of 12 flasks. With this flask you may use rubber stoppers size 6 and 6 1/2.