American Defense Manufacturing Aimpoint Comp M4 Cowitness Riser Black AD-CM4-CO. These Red Dot Sight Mounts by American Defense Manufacturing increase the height of your CompM4 by 0.75" and improves the alignment of the sights for pin-point accuracy. One Aimpoint Comp M4 Riser is required for each riser purchased. Using the Aimpoint CompM4 Riser: Place the riser where you want on the CompM4 and mark the location of the dot where you want the dot to be. There should be a slight gap between the dot centerline and the top of your red dot sight. Then the dot can be lined up without interfering with your shooting position. The bottom of the dot mount where you placed the dot originally has to be centered to the top of your red dot to allow the dot to mount where you want it to. Once you install the dot where you want it you can then come back and adjust the height as needed. This height raises the CompM4 Co-Witness to match the height of your current optic. The white area on the underside of the dot where the light comes through from the sides and bottom of your red dot where the light is supposed to be. Specifications for American Defense Manufacturing Aimpoint Comp M4 Cowitness Riser: Manufacturer: American Defense Manufacturing Color: Black Finish: T3 Mil-Spec Anodize Fabric/Material: 6061-T6 Aluminum Co-Witness: CM4-CO Red Dot Sights-Footprint: Not Applicable Optic Cut: Not Applicable Weight: 0.75 oz Additional Features: Fits Aimpoint CompM4 Package Contents: American Defense Manufacturing Aimpoint Comp M4 Cowitness Riser American Defense Manufacturing AD-CM4-CO: Aimpoint Comp M4 Cowitness Riser Black