Utility gauge (3,5)
I believe the answer is:
gas meter
'utility gauge' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for gas meter that I've seen before include "Bill after its second reading, perhaps" , "Fuel flow measurer" , "Measuring device for fuel used, for heating perhaps" , "Domestic utility device" , "Measurer of fuel consumption" .)