Orion 10109 4.5 to 10-Inch Dob Dolly for Dobsonian Telescopes Rugged wheeled platform makes it easy to move your assembled Dobsonian telescope Compatible with all Orion 4.5", 6", 8" and 10" Dobsonian reflector telescopes three robust threaded risers lift the Dob Dolly and attached telescope above wheels for use as a stable viewing platform Soft rubber castor wheels absorb vibrations for smooth motion Not recommended for off-road use