A shallow steel cylinder, called as POT is inserted with a thinner, neat fitting, disc of Elastomer which has a recess to accept the Sealing Rings. A steel Piston is then inserted into the POT and bears against the Elastomeric disc. The resulting assembly is frequently perceived as being similar to that of an hydraulic fluid sealed within the POT and the PISTON arrangement but is free to rotate about any horizontal axis with minimum resistance which is a highly desirable feature of bridge bearing. By keeping rotational resistance to a minimum, a uniform distribution of load into the structure is ensured.
Pot Bearings are able to absorb construction twists. This is ensured by deforming the embedded elastomeric disc with particularly low deforming resistance.