Our sorption coolers are quite small and we are actively working to minimise the thermal load imposed on the 4K cryocooler stage. We aim to keep the cryocooler thermal demand to a minimum. An RDK101 with 100/160mW of cooling power is adequate for a GL4 or small GL7. For a CC4/7 a PT 405 or 407 with 250/400mW should be more than adequate.