Corning® Pyrex® Ribbed Watch Glasses / Beaker Covers
By CorningFor EPA Methods 3005, 3010, 3020
These ribbed PYREX® watch glasses are designed for use as beaker covers. Ribs are molded into the glass so that they can't pop off as they do when cane is sealed to standard watch glasses. Permits escape of excess vapor and eliminates risk of contamination from dropped hooks or props.