pulley is part of:

pulley contains:

Full expansion for pulley:
   100%  1.5x1.5 Micro-Motor-Style Pulley
    90%  3x3 Technic Pulley
    80%  3x3 Technic Pulley w/ Tires
    80%  4.5x4.5 Technic Steering Wheel
    70%  2x2 Studded Hub w/ Metal Peg
    70%  2x2 Studded Hub w/ Peg Hole
    70%  2x2 Technic Cross-Axle Hub
    60%  Small Tiny-Peg Hub
    60%  2x4 Brick w/ Red 2x2-Stud End Hubs
    50%  1x1x.5 Technic Pulley w/ Toothing
    50%  1x1x.5 Toothless Technic Pulley
    50%  2x2 Round Plate w/ Bottom Pulley
    20%  2x2 Plate w/ Tiny Gray Wheels
    20%  2x2 Technic Cross-Axle Hub w/Lg.Tires
    20%  2x2 Technic Cross-Axle Hub w/Sm.Tires
    20%  3x3 Technic Wheel Hub/Tri-Pulley
    10%  3x3 Rubber Tire for Technic Pulley