This module features the XL6009E1 4 Amp step up (boost) converter, which can take input voltages as low as 5V and step up the output to as high as 35V.
This module has a multi-turn trimpot (potentiometer) that you can use to adjust the output voltage. Since the trimpot has 25 turns of adjustment you can easily adjust the output of the module to exactly the voltage you need.
Boost converters are a great way to easily increase a given voltage, but that boost comes at the cost of less output current compared to input current.
Since this is a boost converter the output voltage has to be higher than the supplied input voltage.