The invention provides a device for extraction of a defined sample volume from a larger sample volume. The device includes a body having a reference surface and a measuring cavity extending from a part of the reference surface into the body, thereby forming at least one opening plane substantially uniform with the reference surface. An information carrier is applied to or distributed with the device, having direct or indirect volume information about defined volume established for the cavity. The invention also relates to a method for determining the volume of such a cavity, to a set of at least two such devices, to a method for dilution of at least two liquid samples by using at least two such devices, to an analytic instrument, to a method for operating such an instrument, to a system including the device and the instrument, and to a method for operating the system.