A heat exchanger, and method of manufacture of a heat exchanger configured to be placed into contact with an object to regulate the temperature of the object. The heat exchanger comprises a layer of material defining a passage through which a heat transfer fluid may flow. The material layer has a first side for contact with the object； and a second side which, in use, will face away from the object. The first side has a relatively high coefficient of thermal conduction. The second side has a relatively low coefficient of thermal conduction compared to the first side.
