A method for fabricating a Coriolis flowmeter from a single polymer material, the method comprising: providing a dynamically responsive manifold from a first polymer material, the dynamically responsive manifold comprising: a body; at least four tubular port extensions integral to the body, each tubular port extension including a weld surface; and at least one isolation plate integral to the body and the at least four tubular port extensions; and characterised by providing at least two flow-sensitive members formed by shaping at least two tubes to a predetermined shape, the at least two tubes made from the first polymer material, and each flow-sensitive member including two open ends; wherein: shaping the at least two tubes to a predetermined shape comprises: heating one of the at least two tubes to a temperature near a glass transition temperature of the first polymer material, forming the tube into the predetermined shape, dissipating mechanical stress within the shaped tube by maintaining the temperature for a time period, and cooling the shaped tube; and in that the method further comprises: welding each open end of the at least two flow-sensitive members to a corresponding weld surface of one of the at least four tubular port extensions. providing a dynamically responsive manifold from a first polymer material, the dynamically responsive manifold comprising: a body; at least four tubular port extensions integral to the body, each tubular port extension including a weld surface; and at least one isolation plate integral to the body and the at least four tubular port extensions; and a body; at least four tubular port extensions integral to the body, each tubular port extension including a weld surface; and at least one isolation plate integral to the body and the at least four tubular port extensions; and characterised by providing at least two flow-sensitive members formed by shaping at least two tubes to a predetermined shape, the at least two tubes made from the first polymer material, and each flow-sensitive member including two open ends; wherein: shaping the at least two tubes to a predetermined shape comprises: heating one of the at least two tubes to a temperature near a glass transition temperature of the first polymer material, forming the tube into the predetermined shape, dissipating mechanical stress within the shaped tube by maintaining the temperature for a time period, and cooling the shaped tube; and in that the method further comprises: welding each open end of the at least two flow-sensitive members to a corresponding weld surface of one of the at least four tubular port extensions. shaping the at least two tubes to a predetermined shape comprises: heating one of the at least two tubes to a temperature near a glass transition temperature of the first polymer material, forming the tube into the predetermined shape, dissipating mechanical stress within the shaped tube by maintaining the temperature for a time period, and cooling the shaped tube; heating one of the at least two tubes to a temperature near a glass transition temperature of the first polymer material, forming the tube into the predetermined shape, dissipating mechanical stress within the shaped tube by maintaining the temperature for a time period, and cooling the shaped tube; and in that the method further comprises: welding each open end of the at least two flow-sensitive members to a corresponding weld surface of one of the at least four tubular port extensions.