A device and a method for a field expansion. A support core (30) is inserted into the device by a field expansion apparatus. The field expansion apparatus has a pressure applying means (20) defining a radially expandable inner surface and a flat surface radially outwardly extending from the radially expandable inner surface. The device comprises an elastomeric tubing (10) and an adapter (40). The elastomeric tubing (10) has a forward end opposite a rearward end and an axial bore extending therethrough configured to receive the support core (30). The adapter (40) has a step portion (41) defined by a radial outer surface (42) and a flat surface (43) radially outwardly extending from the radial outer surface (42), and an axial bore (44) extending therethrough. The axial bore (44) has a diameter substantially the same as the diameter of the axial bore (12) of the elastomeric tubing (10). The adapter (40) is positioned substantially coaxially with the elastomeric tubing (10) between the pressure applying means (20) and the elastomeric tubing (10) such that, in response to inserting the support core (30) from the rearward end into the elastomeric tubing (10), the flat surface of the adapter (40) is pushed against the flat surface of the pressure applying means (20) by the elastomeric tubing (10); the interface between a rearward end of the adapter (40) and the forward end of the elastomeric tubing (10) is of high friction so that the adapter (40) and the elastomeric tubing (10) expand radially in unison, and the radial outer surface of the adapter (40) exerts a radially outward pressure against the radially expandable inner surface of the pressure applying means (20). device and method for field expansion device and method for field expansion