United Scientific™ serological pipettes feature black graduations for precise reading and accurate dispensing. Reverse graduations show volume removed or remaining on all pipettes larger than 1 mL. Negative graduations provide additional pipetting volume. Manufactured from transparent USP Class VI polystyrene and sterilized by gamma irradiation. Each lot is DNase, RNase, & Pyrogen free. Pipettes are individually wrapped in plastic/paper easy-to-peel packs. Manufactured to ASTM Standard Specification for Serological Pipettes E-934.