The HP / Agilent 44491A Armature Relay Multiplexer Assembly consists of eight 2-wire armature relay channels and two current/actuator channels. Maximum voltage (terminal-to-terminal or terminal-to-chassis) is 250 Vrms. The maximum current (per channel) is 1.0 A dc or ac rms. The thermal offset is less than 3 µV. The unit has a closed channel resistance (end of relay life) of less than 2 ohms and a maximum switching and measurement speed of 33 channels/second. The unit is a plug-in for the 3457A Multimeter, sold separately.