Pipette filler these bulb type pipette fillers are tailored for one hand operation. Pipette e fillers improve worker safety by eliminating mouth pipetting and handling of hazardous materials. Users can control air evacuate????on, Liquid uptake, And liquid dispensing with three valves containing chemically resistant stainless, Steel balls. Pinching or releasing valves provides smooth liquid flow. Fits standard size pipettes. Pipe filler with 3 valves valve a release air valve s filling valve e delivery size 50ml