This Vikem® vinyl squeeze-bulb pipette filler has greater chemical resistance than standard rubber bulbs. It accommodates pipettes from 5 to 14mm in diameter. Three pinch valves are coded for use. The filler may be operated with one hand by pinching valve control pad "A" with your thumb and index finger while squeezing the bulb with three fingers and palm. The bulb will remain collapsed when pad "A" is released. Then squeeze pad "S" to aspirate liquids into the pipette. Squeezing pad "E" dispenses liquid from the pipette. Bulb is 54mm (2 1/8") in diameter, overall length is 152mm (6").