They consist of two ring-shaped stainless steel plates welded together around their circumference. The anular space between the plates is filled under vacuum by deaired oil. The load is directly measured by a Bourdon manometer connected to the cell body.

The manometer is calibrated in laboratory to allow direct readings in KN. Electrical models equipped with pressure transducer is also available for remote readings. A very stiff distribution plate is supplied, in order to ensure that the load is applied equally over the loading surface of the cell.