axle is part of:

axle contains:
    50%  cross-axle
    50%  wheel-axle
    12%  cross-axle-hole  (indirectly)

Full expansion for axle:
    50%  #10 Technic Axle
    50%  #12 Technic Axle
    50%  #14 Technic Axle
    50%  #16 Technic Axle
    50%  #2 Notched Technic Axle
    50%  #2 Technic Axle
    50%  #3 Technic Axle
    50%  #4 Technic Axle
    50%  #5 Technic Axle
    50%  #6 Technic Axle
    50%  #8 Technic Axle
    50%  2x2 Plate w/ Metal Axle & Lg Tires
    50%  2x2 Plate w/ Metal Axle & Sm Tires
    45%  3L Technic Axle w/ End Stud
    40%  #1 Technic Axle w/ Ball
    40%  2L Technic Axle/Peg
    40%  2x2 1-Wheel Landing Gear Axle
    40%  2x2 2-Wheel Landing Gear Axle (Front)
    40%  2x2 2-Wheel Landing Gear Axle (Side)
    40%  2x2 Landing Gear Axle in Tri-Set
    35%  #4 Technic Axle w/ Dual End Sockets
    35%  3L Technic Catch
    30%  2L Technic Piston Crank w/ Axle
    12%  #1 Technic Angle Joint (End)
    12%  #2 Technic Angle Joint (180 deg.)
    12%  #3 Technic Angle Joint (157.5 deg.)
    12%  #4 Technic Angle Joint (135 deg.)
    12%  #5 Technic Angle Joint (112.5 deg.)
    12%  #6 Technic Angle Joint (90 deg.)
    12%  2L Ribbed Technic Axle Extender
    11%  1.5x1.5 Micro-Motor-Style Pulley
    11%  1x1x.5 Technic Pulley w/ Toothing
    11%  1x1x.5 Toothless Technic Pulley
    11%  1x1x1 Technic Stop Bushing
    11%  1x2 Brick w/ Side Technic Axle Hole
    11%  2L Technic Crank/Skew Connector
    11%  2L Technic Cross-Block Connector
    11%  2x2 Technic Cross-Axle Hub
    11%  3L Technic Cross-Block Connector w/ Nibs
    11%  4L Technic Universal Joint
    10%  1x1x2.3 Changeover Catch
    10%  2L Technic Cross Catch
    10%  2L Technic Toggle Joint
    10%  2x2 Technic Cross-Axle Hub w/Lg.Tires
    10%  2x2 Technic Cross-Axle Hub w/Sm.Tires
    10%  2x2x3 Jet Engine Turbine w/ Axle
    10%  2x3 Cam
     9%  2L Technic Piston Rod w/ 2 Side Studs
     9%  3x3 Technic Steering Wheel
     9%  4.5x4.5 Technic Steering Wheel
     6%  2x2 Cyl.Brick w/ BlackBox, 2x4 Gray Dots
     6%  2x2 Cylinder Brick
     6%  3x3 4-Knob Wheel w/ Axle Hole
     6%  3x3 Technic Pulley
     6%  3x3 Technic Wheel Hub/Tri-Pulley
     6%  3x3 Thin-Disc w/ Center Axle-Hole
     5%  3x3 Technic Pulley w/ Tires
     5%  4x4 Technic Hub w/ "43.2x28 S" Tire
     5%  5x5 Technic Hub w/ "68.8x40 Q" Tire
     4%  Aquazone-Style Propellor
     4%  4x4x1.3 Grooved Hub w/ 7 Peg Holes
     4%  4x4x1.6 Grooved Hub w/ 7 Peg Holes
     4%  4x4x2 Cylinder Hub w/ 6 Peg Holes
     3%  2x2 Brick w/ Propellor Housing
     2%  3-Blade Rotor-Plate w/ Toothing
     2%  4x4 Dome-Backing Disc w/ 1x2 Plate
     2%  4x4x1 Cylinder Brick w/ 4 Peg Holes
     2%  4x4x2 Cowling w/ Axle Hole
     2%  1x5 Plate w/ End Holes & Toothing
     1%  2x5x2 Strut w/ Sleek Conical Engine