PYREX® Reusable Large Tip Opening, Color-Coded Serological Pipets are made with a large tip opening to allow more rapid intake and delivery of suspensions and viscous materials. Color coded by size for easy identification and sorting. Colored graduations are enameled onto the glass. The two narrow bands or one wide band at the top indicate the pipet is calibrated “to deliver” its total capacity when the last drop is blown out. WARNING: Do not pipet by mouth, we suggest using a mechanical pipetting device.