The LNF-TERM4_12A is a termination suitable for converting an LNF circulator into an isolator with a DC feed through. The DC voltage will be present at both the input and output of the isolator. They have been designed from ground up to meet the strict requirements of ultra-low temperature physics research. The gold plated OFHC copper body ensures minimum loss and that this loss reaches the lowest possible temperature to minimize thermal noise. The module measures 9.5 mm * 9.5 mm * 31.4 mm excluding the connectors.