The present invention provides a flowmeter for determining a fluid flow rate through an associated valve assembly, the flowmeter comprising a housing; a sensor arrangement disposed in the housing, the sensor arrangement comprising at least one sensor configured to detect a quantity indicative of the fluid flow rate through the valve assembly; and an coupling portion provided at the housing and configured to engage with an associated counter-coupling portion of the valve assembly for selectively attaching the flowmeter to the valve assembly in an orientation selectable from a group comprising at least a first orientation and a second orientation. The present invention also provides a valve assembly having a counter-coupling portion configured to receive an associated coupling portion of the flowmeter for selectively attaching the flowmeter to the valve assembly in any one of at least a first orientation and a second orientation. An inlet valve provided by the present invention comprises the flowmeter and the valve assembly, wherein the flowmeter is attached to the valve assembly in either one of the first or second orientation.