How to use Flip inside modeler
To use Flip inside modeler
Multiply > Modeler > Detail > flip or press (f)
If you would like to use the flip inside modeler, first you need to go to the Modeler option from the Multiply. Later, you need to choose the Flip option under the Detail menu or just press (f) to select the Flip tool. This tool is used for to flip the polygon from one side to another as shown by the picture below.
You could see that the picture shows how one side of the polygon has been flipped from one side to other.