Pipette tip couplers, pipette tips, coupler and tip combinations, and methods for coupling and decoupling a pipette tip to or from a pipette tip coupler mounted on a pipette device. The pipette tip couplers include a proximal elastomeric element, a distal elastomeric element, and a coupler stop shoulder surface between the elastomeric elements. The pipette tips include a groove in a first cylindrical section, a second cylindrical section, a tip stop shoulder surface at the interface of the first and second cylindrical sections, a third cylindrical section distal to the second cylindrical section, and a sealing seat surface at the interface of the second and third cylindrical sections. When the pipette tip is mounted on the pipette tip coupler, the proximal elastomeric element abuts the tip groove, the coupler stop shoulder surface abuts the tip stop shoulder surface, and the distal elastomeric element abuts the sealing seat surface.