Here's a list of Aeron chair parts pertaining to the arms:
Arm pads with fasteners (leather, vinyl, fabric, or knit)
Arm-adjustment hardware and bushings
Left-hand and right-hand arm pad supports
Left-hand and right-hand adjustable arm yoke (aluminum, graphite, or titanium)
Left-hand and right-hand swing arm (aluminum, graphite, or titanium)
Swing arm bearing set
Arm index hardware set
Here's a list of Aeron chair parts pertaining to the seat and back:
Seat frame (A, B, or C size; graphite or smoke)
Back frame (A, B, or C size; graphite or titanium)
Seat frame applique (A, B, or C size; graphite or smoke)
Back-mounting hardware (black or titanium)
Seat-frame fasteners (black or titanium)
Rear seat link mounting hardware
Left-hand and right-hand seat link
Front-seat link mounting hardware (black or titanium)
Adjustable lumbar pad
Seat foam insert (A/B size or C size)
Here's a list of Aeron chair parts pertaining to the base, cylinder, and levers:
Base (A size or B/C size; aluminum, graphite, or titanium)
Pneumatic single-stage cylinder cartridge
Two-stage pneumatic cylinder cartridge
Cylinder removal tool
Gas cylinder replacement bearing kit with rubber bumper cushion
Control assembly (graphite or smoke)
Tilt (A, B, or C size)
Tilt covers (graphite or smoke)
Tilt spacer (graphite or smoke)
Forward tilt knob and lever (black or smoke)
Tilt limiter knob and lever (black or smoke)
Here's a list of Aeron chair parts pertaining to the casters and other miscellaneous parts:
Standard caster
Standard braking caster
Hard-floor soft caster
Hard-floor soft braking caster
3-inch deep carpet hard plastic caster
Touch-up paint (black or graphite)
Pellicle mesh repair kit
Bearing grease lubricant
Hip pivot bearing
Pneumatic cable assembly
Pneumatic control knob
Pneumatic clip
Trim bushing
Bevel gear/T-shaft
Front limit cam
Rear limit cam
Sector gear and cable