MOAG means Manual Off-Axis Guider. It allows you to guide your telescope to obtain sharp, round stars by guiding in front of your filters using unfiltered light in the same optical beam as your imaging camera.
MegaMOAG 3" to 4" Off-Axis Guider
The MegaMOAG takes the design of the MonsterMOAG and adapts it for telescope systems with larger optical openings. It comes with the same camera-side adapter as the MonsterMOAG but it has a 4" opening on the scope side. The body is larger and the pick-off prism is further from center. It has the same 1.25" body thickness as the MonsterMOAG. It comes with a single guide port. As with the MonsterMOAG, a black metal plate will cover the unused ports for the MeMOAG. Additional port assemblies can be added at a later time with the MonsterMOAG Extra Port Assembly (MMOAG-PORT) to make up to a 4 port MeMOAG.