Minimum weight of Nano Board (without IO board and heatsink)

Hi thais15, the weights are as follows:

Module without heatsink.......15 grams
Heatsink, 4 screws & spring...46 grams

So the weight of the module + heatsink/screws/spring is 61 grams.

It is not recommended to attempt running the module without some form of heatsink or cooling. You could try a smaller heatsink though.