The MAX3232CSE (marked as U1 on the PCBa) can operate between 3.3VDC and 5.0VDC.
Draws around 6mA. The capacitors (marked as C1 ... C5 on the PCBa) that are needed by this
device are surface mounted on the PCBa. Also, a little
surface mount LED. This lights up red when power is applied. The LED has the typical current limiting resistor fitted as R1.
You need to supply DC power to the module using the 0.1" pins.
Four pins in all TXD, RXD, GND, VCC. Clearly marked on the PCBa.
The module measures approx 33mm x 32mm x 16mm and has a couple of pre-drilled mounting holes.
The DB9 female connector has the usual hex screws to allow an external cable to be held in place.