Compensators will make up the gap between the shower doors and the walls, giving you space to make fitting adjustments and achieve a finished appearance. Compensators are U-shaped channels, open on one long edge. Each door assembly's end fits into a compensator channel. With the doors removed, you have access into each channel to fasten the compensators to the walls. When you slip a door assembly into a compensator, you can fine-tune its position so that the door's gasket rests on the floor and so that the door will swing properly.