Abstract: A method and a device for better utilizing latent cold in a cold producing material used for producing and upholding a pre-determined temperature inside a transport container or the like, where dry ice or a similar first phase change material having very low sublimation temperature is utilized. Inside the transport container is arranged a receptacle for such low sublimation temperature phase converting material, the said receptacle being provided with an enclosure having cavities for a second phase change material having a considerably higher melting point, the said cavities of the receptacle at least partially enclosing the inside of the receptacle, in which the converting material having the essentially lower melting point is received.