BrandTech 4721450 25mL Adjustable Volume Pro Bottletop Dispenser, For Laboratories Capacity: 2.5-25ml Features an easily-replaceable wiping seal dispensing cartridge, making it especially suitable for liquids that tend to form crystals Quick-change cartridge; pump assembly with corrosion resistant spring Valves and seals on the seripettor pro allow a broader range of liquids to be dispensed than the regular seripettor Threaded safety cap attaches and removes with a quick twist. Spring-loaded piston permits one-handed, semi-automatic operation