Abstract: A pipetting system with a pipetting device and at least one pipette tip releasably fastenable thereon, at least one fastening element on the pipetting device, on which the pipette tip is fastened, an ejection means on the pipetting device, which has an axially movable ejection element for releasing the pipette tip from the fastening element with an axial movement of the ejection element and a drive means for driving the axial movement of the ejection element, and a pull-means gear, push-means gear or linkage gear which transmits an essentially axial drive movement of the drive means into an axial movement of the ejection element and with which the ejection element at least on releasing the pipette tip from the fastening element is axially movable over a smaller distance than the essentially axial drive movement covers and an ejection force exceeding the force for the essentially axial drive movement can be exerted onto the pipette tip.

Abstract: A plastic pipette tip easily and firmly mountable on and easily ejectable from a pipette mounting shaft of a pipette by application of relatively small axial mounting and ejection forces of about six and three (3) pounds respectively. The pipette tip includes a tubular proximal portion comprising (i) a frusto-conical open upper end portion having an inner diameter at its upper end greater than the diameter of a mounting shaft of the pipette to which the pipette tip is to be mounted, (ii) a hollow mid-portion and (iii) an annular sealing region at a junction of the open end and mid-portions. The annular sealing region has an inner diameter less than “x” and is designed to engage a lower end of a sealing zone of the mounting shaft to stretch radially outward as the mounting shaft is guided and stably oriented in the proximal portion thereby creating a fluid tight seal between the sealing zone and the sealing region.

Abstract: An air displacement pipette having axially spaced annular sealing and substantially cylindrical lateral support zones and regions on the pipette's mounting shaft and tip, respectively, in combination with structure for insuring uniform depth of mounting shaft penetration into the pipette tip to maintain uniform tip interference with the mounting shaft as successive tips are mounted on and ejected from the mounting shaft whereby the pipette tip is easily and firmly mountable on and easily ejectable from the pipette tip mounting shaft by the application of axial mounting and ejection forces of about two pounds and one pound, respectively.

Abstract: An air displacement pipette having axially spaced annular sealing and substantially cylindrical lateral support zones and regions on the pipette's mounting shaft and tip, respectively, in combination with structure for insuring uniform depth of mounting shaft penetration into the pipette tip to maintain uniform tip interference with the mounting shaft as successive tips are mounted on and ejected from the mounting shaft whereby the pipette tip is easily and firmly mountable on and easily ejectable from the pipette tip mounting shaft by the application of axial mounting and ejection forces of about two pounds and one pound, respectively.