These PYREX VISTA 10 mL, 25 mL, 50 mL, 100 mL, 200 mL, 250 mL, 500 mL, 1000 mL, and 2000 mL volumetric flasks provide precise volume measurement. These flasks have sealed necks tooled for No. 9, No. 13, No. 16, No. 19 No. 22, and No. 27 Standard Taper glass stoppers. The graduation line is sharp and permanent and large blue block letters make the inscription easy to read.