Things You'll Need
Instructions
Connect a grey 2-by-1 plate to one 2-by-2 round green plate.
Connect one grey 1-by-1 roller plate to one of the two remaining visible studs on the green round plate. The roller plate looks like a square with a roller or tube extending from it. Connect a 1-by-1 grey plate to the last remaining visible stud of the green round plate.
Connect a 2-by-2 round green brick to the top of the grey plates.
Connect a 2-by-2 yellow round plate to the top of the round green brick.
Connect a 2-by-2 brown plate to the top of the yellow round plate.
Connect another 2-by-2 brown plate on top of the brown plate you just placed.
Connect a 2-by-2 round green plate on top of the last brown plate you connected.
Connect a 1-by-1 round green dome brick to the top of the green round plate you just connected. The round green dome brick has one stud on top and four depressions on the bottom. Connect a lever to the top stud of the green dome to complete your R1-G4.