I did this with an old 5w module…
Remove the module from the gantry. Set the power at about 10% and point it at a wall about 6’-10’ away. You will then see the true pattern of the laser beam shape. It is definately not a dot or oval.
Not for a 20w laser, which is where they try to focus 4 diodes to 1 spot. In my opinion, they understated the size.