[en] A single stage, twin piston Stirling refrigerator, producing several mW of refrigeration at 3 to 4 K and rejecting 50 to 100 mW at 8 to 14 K is described. The working fluid is helium. The operating temperature is essentially the equilibrium vapour temperature of helium at the average pressure. For example 3.1 K was achieved at average pressure of 0.027 MPa and 4 OK at 0.08 MPa. The hot end temperatures were 8.6 and 12 K respectively. (U.K.)