The PRGS Projector Mount simplifies the way image alignment is done. The precision gear design allows exact pitch and roll image positioning by either simply turning two adjustment knobs with a Phillips screw driver, or using the tool-less option by extending the knobs to adjustby hand. Just set the precision gear to the desired position to secure it in place. It will hold its position even during projector maintenance. With Peerless-AV® PRGS Projector Mount, just set it and forget it. No more adjustment screws. No more micro adjustments. No more hassles.All projectors with M8 mounting screws require ACC-M8RI inserts for compatibility with any Peerless-AV projector mount, please refer to the Recommended Accessories.