The QMC-CRYOTEE-0010 from Quantum Microwave is a Cryogenic Bias Tee that operates from DC to 500 kHz (DC path) and from 3 MHz to 10 GHz (RF path). It can handle a DC voltage of ±20 V and a current of up to 600 mA. The bias tee has an insertion loss of less than 1 dB and can operate at temperatures as low as 10 mK. It is available in a gold-plated OFHC package that measures 1.10 x 0.63 x 0.48 inches and has SMA (male and female) connectors.