Abstract: An assembly for transferring data comprises a measurement data acquisition unit in the form of a portable measuring device, a measurement data processing unit, and an auxiliary unit for transferring data between the acquisition unit and the processing unit. Contact-less coupling elements are operatively associated with the acquisition and auxiliary units respectively for transferring measurement data between the acquisition unit and the auxiliary unit by contact-less coupling. Data are transferred between the auxiliary unit and the processing unit. The auxiliary unit includes a connecting member for mechanically detachably connecting the auxiliary unit with the acquisition unit such that the contact-less coupling elements face one another at a predetermined spacing and such that the connected acquisition and auxiliary units together form a portable measuring device.