manikk Dual Multiple 1 to 3 is a 2HP module that has 2 active buffered multiples. Each multiple have 1 input and 3 outputs.
The output from the upper multiple (jack 4) is normalized to the input (jack 5) of the lower multiple. If no plug is inserted in the input at jack 5, then the upper multiple is extended with 3 more outputs, 6 outputs in total.
The two inputs have a 10M resistor to GND, that makes the OP-amps happy when no input signal is connected.
Each of the outputs have a 1K resistor before the signal is sent to the jack.
The dual row pins on the bottom of the backside is the regular eurorack power connector. The negative -12V is marked on the backside of the PCB. The power cable usually has a red stripe for the negative -12V. Make sure to get the orientation correct.